MedWorm.com provides a medical RSS filtering service. Over 5000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Sciencesque' source. Sat, 16 Aug 2008 14:47:17 +0100 http://sciencesque.wordpress.com/2007/04/16/this-just-breaks-my-heart/ I just heard about the senseless shootings at Virginia Tech, and am left dumbfounded as to why these tragedies occur at our schools and universities (or at all, for that matter). I want extend my condolences to the family and friends of the victims and wish them all the strength and love they’ll need to get through this time of loss. Blogged with Flock Tags: Virginia Tech, shooting (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=547564 Mon, 16 Apr 2007 23:20:32 +0100 547564 http://sciencesque.wordpress.com/2007/04/15/oekologie-40-blog-carnival-is-available/ Matt has posted the 4th edition of Oekologie at his Behavioral Ecology Blog. Although I don’t often delve into matters ecological, I submitted two Hinterland Who’s Who-related articles to this new blog: Hinterland Who’s Who - The Beaver, and Moose to be moved to the “Hinterland Has Been” list?. Check out the rest of this carnival for the best in environmental science blogging. Blogged with Flock Tags: blog carnival, Oekology, ecology, environment, zoology, climate change, global warming (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=545335 Sun, 15 Apr 2007 15:33:54 +0100 545335 http://sciencesque.wordpress.com/2007/04/13/sequencing-dinosaur-proteins/ Alex at The Daily Transcript has an interesting post on how the Lewis Cantley lab at Harvard has sequenced proteins isolated from the fossilized bone of a Tyrannosaurus Rex that lived, loved and died 68 million years ago. They also did the same on mastodon bones that are thought to be be 160,000-600,000 years old. The NY Times story can be read here, while the original report in Science can be found here. Previously, it was felt that even under the most ideal conditions, reliable biological samples could not be retrieved from specimens older than 1 million years. This is because complex biological molecules such as proteins and DNA tend to degrade over time to the point that they are no longer detectable. What’s really amazing about this break through (if contamination has not been an issue) is that the 1 million year time limit has been pushed back to 68 million years. That’s a remarkable jump back in time. However, we shouldn’t expect to hear about new ancient protein sequences popping up every week, since the fossilization and preservation conditions have to be just right in order to prevent the breakdown of soft tissues. From the NY Times article: “Mr. Horner suggested that the size of the bone and the depth of its entombment accounted for the unusual preservation of the tissues. Thick bones, he said, afford interior matter more protection from environmental degradation. Another factor was that this particular dinosaur was buried in a virtually oxygen-free setting very soon after death. The depth may also have insulated it over time. Mr. Horner said paleontologists should look for other candidates for soft tissue retrieval among remains of the largest dinosaurs resting under tens of feet of rock. Such excavations, he conceded, will not be easy.” The researchers also used the protein sequence information they generated to do a bit of phylogenetic analysis. They found that the T-Rex collagen protein (a major component of bone) is related to that of chicken. However, this finding is considered a little on the “insignificant” side, since it is already widely-accepted that present-day birds are descended from the dinosaur lineage. Blogged with Flock Tags: dinosaur, chicken, T-rex, tyrannosaurus rex, protein, DNA, ancient, Lewis Cantley, sequencing, mastodon, bones, fossils, evolution (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=541637 Fri, 13 Apr 2007 19:23:10 +0100 541637 http://sciencesque.wordpress.com/2007/04/11/inner-life-of-the-cell-video/ This video rocks my inner world! All those molecules, proteins, genes, etc. that molecular biologist go now and now about are put into context in this 3 minute journey inside a computer-generated cell. A longer version with descriptive narration is also available for your viewing pleasure. Via Science Blog. Tags: science, biology, molecular biology, cell, biochemistry, video, YouTube, education (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=538563 Thu, 12 Apr 2007 00:06:23 +0100 538563 http://sciencesque.wordpress.com/2007/04/09/encephalon-20-blog-carnival-available-at-neurontic/ The 20th issue of Encephalon is available at Neurontic. This carnival is focused on the brain, neuroscience and psychology. My contribution is one of the random Gene Genie expeditions I’ve gone on, specifically the role of Gbx2 in positioning the midbrain-hindbrain boundary. (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=531367 Mon, 09 Apr 2007 22:56:45 +0100 531367 http://sciencesque.wordpress.com/2007/04/08/framing-science-a-new-skin-for-the-old-ceremony/     The blogosphere is all lit up with views and commentary on the “Framing Science” article by Matthew Nisbet and Chris Mooney. Interesting discussion can be found at Sandwalk, A Blog Aroung The Clock (and links within), Pharyngula, as well as Matthew Nisbet’s site. Essentially, the article argues that scientists are losing the battle of popular opinion because they don’t frame science in a way that normal folk can relate to. People glaze over when someone start to talk science. Unless scientists and science writers get better at communicating with the public, so the argument goes, we will lose valuable mind-space to interests that are better “framers”, such as Conservative politicians and the Intelligent Design movement. If only scientists could choose better words, use friendlier concepts, and be more inclusive, surely everyone would see things our way, and society would be ruled by the concepts of pure science and reason.     As far as I can tell, “framing” is little more than a neo-term for rhetoric, a.k.a. “spin”. Nisbet and Mooney have framed rhetoric in a new way to make it new and exciting for scientists again. Allow me to frame the issue in a different way using a favourite device of rhetoricians everywhere: the analogy. Science is like that smart kid in the class that no one likes. The only reason anyone talks to Science is to get help with their homework, and she is only too happy to oblige. But Science has this bad habit of rambling on about things that seem important to her, but unless it relates directly to their homework, the other students have better things to do. Despite Science’s best intentions, the rest of the class see her as arrogant, impenetrable, and even threatening, albeit useful from time to time.     To bring this analogy back into the real world, unless science has assured the world faster porn downloads or a cure for cancer, the majority of people simply are not interested. People want their science useful, or not at all. In their article, Nisbet and Mooney contrast the rhetoric scientists have used to defend their positions on evolution and embryonic stem cell research. They suggest that scientists have failed in the debate on evolution because they have been arguing the science instead of the cost of creationism to society and the taxpayer. On the other hand, by framing the debate over stem cell research in terms of  “social progress” and “economic competitiveness” (not to mention the possible health benefits), scientists have been quite successful in securing funding dollars, even when faced with attacks from the right-wing. So, what Nisbet and Mooney are saying is that we need to drape science in a utilitarian shroud, whether that be financial, social, or medical.     This doesn’t seem especially novel to me, and just sounds like good sense. Of course scientists should expound the utility of their work; that’s a good part of why science is done (the other part is curiosity). But when we do frame science in this way, it should always be done within the super-frame of accuracy and truthfulness. I doubt that Nisbet and Mooney are advocating anything different. However, I will say that the idea that “framing” science properly will suddenly illuminate where science don’t shine is really a very arrogant (or perhaps naive) one. Science is intimately bound up with reason, and once we step outside its limits, we find ourselves surrounded by pseudoscience, superstition and religion. Reason simply isn’t welcome here, and even the most well-reasoned, utilitarian rhetoric will likely fall on deaf ears. Many people are still going to feel threatened by that smart kid in the class whether she is useful or not. That’s not to say we shouldn’t try though. Certainly, the goal of every science writer is to make science accessible to the general public, and a worthwhile goal it is. Rhetoric has always been a useful tool in this respect. However, I caution that if rhetoric were the magic bullet, there would have been no need for Nisbet and Mooney to write their article in the first place. Blogged with Flock Tags: science, communication, framing, Matthew Nisbet, Chris Mooney, rhetoric, reason, truth, Intelligent Design, creationism, evolution, stem cells (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=529716 Sun, 08 Apr 2007 22:37:27 +0100 529716 http://sciencesque.wordpress.com/2007/04/08/gene-genie-4-available-at-sandwalk/ The fourth issue of the Gene Genie is up at Sandwalk. This blog carnival hopes to report on all of the genes in the human genome by 2082. Eleven genes are covered in issue 4, leaving approximately 23,900 to go. That means we need more bloggers to tell us about their favourite genes. If you are interested in submitting a gene-related article for the next issue, or hosting a future Gene Genie, please visit the carnival site. Blogged with Flock Tags: Gene Genie, blog carnival, genes, disease, genome, science, biology, genetics (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=529717 Sun, 08 Apr 2007 19:10:20 +0100 529717 http://sciencesque.wordpress.com/2007/04/07/a-nice-looking-pill-to-swallow/ Darzso has a number of really nice photos guaranteed to appeal to the doctor and pharmacist in all of us. You can visit her photoblog here. (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=528404 Sat, 07 Apr 2007 20:08:14 +0100 528404 http://sciencesque.wordpress.com/2007/04/05/poplar-leaf-miner-2/ Poplar leaf miner Originally uploaded by aroid. This is just a beautiful picture. Check out this photographer’s other work for more nature-related images. (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=524551 Fri, 06 Apr 2007 00:07:29 +0100 524551 http://sciencesque.wordpress.com/2007/04/05/the-moose-to-be-removed-from-the-hinterland-whos-who-list/ The plight of the poor moose dominated the front page of the Edmonton Journal yesterday (April 3). The miserable moose on the cover has rubbed itself raw trying to rid itself of its ticks. Unusually warm winters and springs over the past couple of years has increased the Winter tick (Dermacentor albipictus) population in Alberta. Moose are a favourite source of food of ticks, with a single moose having up to 40,000 of the little critters burrowed into their skin. This number of ticks can consume approximately 40 litres of blood over the course of their lifecycle. This means that an infected moose must replace their entire 32L blood supply over the winter months. This comes with an energetic cost that can leave some moose in a diseased state (called “ghost moose”). Usually, only the sick and young are susceptible to tick infestation, but unfortunately, we’ve had a rather cold and snowy winter this year, leaving even healthy adults vulnerable to the tick onslaught. The combination of ticks and cold has ravaged the moose population, not only here, but elsewhere as well. Apparently, the situation is so grave that the Edmonton Journal saw fit to plaster “MASS EXTINCTION FEARED” all over the front page. I might be mistaken, but I thought that “extinction” meant that a certain species had no more surviving members, a situation I doubt is going to happen here. However, the problem is certainly very serious and widespread. For more information on the Winter tick and the problems it causes for wildlife ugulates, see this University of Saskatchewan website dedicated to the subject. Hopefully, weather conditions will change over the next few years to make the climate less favourable for ticks, and the moose population can start its recovery. With any luck, we won’t have to move the moose from the “Hinterland Who’s Who” list to the “Hinterland Has Been” list. Technorati: Hinterland Who’s Who, moose, Canada, environment, wildlife, conservation, tick, Dermacentor albipictus, Winter tick, ungulates, Edmonton Journal, Alberta, biologyextinction (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=524553 Thu, 05 Apr 2007 22:40:02 +0100 524553 http://sciencesque.wordpress.com/2007/04/04/random-omim-search-term-of-the-day-amber/ I’d say it’s time to pay the Random Word Genie another visit, so let’s do that now. With what word shall I search the OMIM database, oh great Genie friend? Um, the Genie revealed unto me that I shall search the OMIM database with the term “amber“. Thus instructed, let’s venture into the vast expanse of the human genome… Ah, time for me to learn something new. The Genie has shepherded me into the land of oral health and tooth development. Top hit for the term “amber”? DENTINOGENESIS IMPERFECTA, SHIELDS TYPE III a.k.a DGI-III or BRANDYWINE TYPE DENTINOGENESIS IMPERFECTA. DGI-III was first described in some citizens of in the quaint town of Brandywine, MD by R.J. Hursey et al. (1956), and again in 1966 by C.J. Witkop et al. This dental disorder affects both the deciduous (baby) and permanent teeth, and causes rapid wearing or breakage of the enamel with eventual exposure of the dentin (also spelled dentine) and pulp. The teeth are also severely discoloured (”amber” coloured), and can also be translucent. There is no effective treatment for the disease other than to crown the teeth. Cross section through a normal tooth (via Wikipedia) Child patient with Dentinogenesis Imperfecta The phenotype of Dentinogenesis Imperfecta Type III is very similar to another disorder known as Dentinogenesis Imperfecta Type II. Both are autosomal dominant diseases caused by mutations in the DENTIN SIALOPHOSPHOPROTEIN (DSPP) gene. DGI Type III can be differentiated from Type II on the basis of multiple pulp exposures and nonmineralization of the pulp chambers. However, it is currently a matter of debate whether DGI Type II and III are the same or distinct disorders. Kim et al. (2005) suggest that Types II and III are phenotypic variations of the same disease, and present evidence that a single DSPP mutation (c.52G–>T, p.V18F) can cause Type II in one family, but Type III in another. This finding suggests that genetic background may be an influencing factor in the phenotypic manifestation of DGI. The DSPP gene is found at human chromosome 4q21.3, a region considered to be a genetic hotspot for dental diseases since there are a number of dental structural genes that map to this area (MacDougall, 2004). The DSPP gene itself is expressed almost exclusively in the teeth by the ectomesenchymal derived odontoblast cells. There is also a very low level of expression in the ear, which may account for why some mutations in DSPP can cause deafness. What’s interesting about DSPP is that the cDNA is translated as a 1253 amino acid protein that is post-translationally cleaved to produce two distinct products, the two major noncollagenous structural dentin proteins dentin sialoprotein (DSP) and dentin phosphoprotein (DPP) (MacDougall et al., 1997). The lack of DSP and DPP causes a softening of the dentin layer leading to brittle teeth and rapid wear. References: Hursey, R.J., et al. (1956) Dentinogenesis imperfecta in a racial isolate with multiple hereditary defects. Oral Surg. 9: 641-658. Kim, J.W., et al. (2005) Mutational hotspot in the DSPP gene causing dentinogenesis imperfecta type II. Human Genetics 116: 186-191. MacDougall, M., et al. (1997) Dentin Phosphoprotein and Dentin Sialoprotein Are Cleavage Products Expressed from a Single Transcript Coded by a Gene on Human Chromosome 4. Journal of Biological Chemistry 272: 835-42. MacDougall, M. (2003) Dental structural diseases mapping to human chromosome 4q21. Connect Tissue Res. 44 Suppl 1: 285-91. Witkop, C. J., Jr., et al. (1966) Medical and dental findings in the Brandywine isolate. Ala. J. Med. Sci. 3: 382-403. Xiao, S., et al. (2001) Dentinogenesis imperfecta 1 with or without progressive hearing loss is associated with distinct mutations in DSPP. Nat Genet. 27: 201-4.   Technorati: OMIM, Online Mendelian Inheritance in Man, gene, Gene Genie, genetics, disease, health, oral health, teeth, dentistry, dentin, DGI, Dentinogenesis Imperfecta, DSPP, dentin sialophosphoprotein, odontoblast, mutation, autosomal dominant, dentation, Brandywine (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=521988 Wed, 04 Apr 2007 20:48:37 +0100 521988 http://sciencesque.wordpress.com/2007/04/03/gene-genie-4-is-just-around-the-corner/ Gene Genie #4 will be hosted at Sandwalk this weekend. Get your gene-related articles submitted by April 4th and join the Gene Genie wave! Blogged with Flock Tags: Gene Genie, blog carnival (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=519253 Wed, 04 Apr 2007 00:29:37 +0100 519253 http://sciencesque.wordpress.com/2007/04/02/hinterland-whos-who-the-beaver/ One of my favourite things as a kid were the Hinterland Who’s Who wildlife films shown on the CBC in the 1970’s. These 60 second shorts provided information on the habitat and behaviour of a Canadian wildlife species, and helped to instill millions of Canadian children with a healthy sense of reverence for nature and all of her creatures. The serene opening flute music and the deadpan-calmness of narrator John Livingston are icons of Canadian culture which many have deemed suitable as fodder for parody and satire (often with hilarious results!!!). Of course, parody is the sincerest form of flattery, and these films have a unique style and mystique that you just can’t find anywhere else. The genius of these shorts is their use of silence. Some more recent incarnations of Hinterland Who’s Who targeted at today’s youth tend to fill everything up with canned drums beats and narration. This is unfortunate, but probably necessary if there is any hope to cut through the din of video games and iPods. I thought I would post a few of the original vintage films for those who grew up without the benefit of the CBC, and for those Canadians who want to get back in touch with our glorious wildlife. The first video I’ll post is about our national animal, the Canadian Beaver. And here’s an interesting tidbit about the beaver that John Livingston doesn’t tell you about. As some of you might know, Catholics aren’t supposed to eat meat on Fridays as an act of penance for their sins. Oddly enough, fish does not fall under the category of meat, and is permissible to eat under Catholic law. This probably has to do with some distinction between the flesh of warm-blooded animals and that of fish and other cold-blooded creatures. Not to mention the “lust” factor! I quote from The Summa Theologica of St. Thomas Aquinas: “…fasting was instituted by the Church in order to bridle the concupiscences of the flesh, which regard pleasures of touch in connection with food and sex. Wherefore the Church forbade those who fast to partake of those foods which both afford most pleasure to the palate, and besides are a very great incentive to lust. Such are the flesh of animals that take their rest on the earth, and of those that breathe the air and their products, such as milk from those that walk on the earth, and eggs from birds. For, since such like animals are more like man in body, they afford greater pleasure as food, and greater nourishment to the human body, so that from their consumption there results a greater surplus available for seminal matter, which when abundant becomes a great incentive to lust.” So, where does the church stand on the consumption of beaver during fasts? Strangely, for the purposes of Catholic dietary requirements, the beaver was considered to be a relative of fish. Apparently, beaver does not promote an excessive amount of lust or pleasure of the flesh. The Wikipedia article on the beaver suggests that this strange fellowship between beaver and fish is also based on the Summa Theologica, where St. Thomas tended to classify animals based on both their morphology and habitat. Since beavers live in the water, and swim around a fair bit, they must be more fish than flesh. Ergo, it’s OK to eat beaver on Friday! Technorati: Hinterland Who’s Who, beaver, Canada, environment, wildlife, conservation, Catholic, Catholicism, St. Thomas Aquinas, Summa Theologica, fish, fasting, John Livingston, Church, CBC (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=517774 Tue, 03 Apr 2007 03:12:54 +0100 517774 http://sciencesque.wordpress.com/2007/03/25/the-gene-genie-reveals-our-genetic-future-at-genetics-health/ Although I missed the submission deadline (yes, I’m looking at you Sadie), I am happy to report that issue 3 of the Gene Genie is up at Genetics & Health. Thanks to Hsien Hsien Lei for putting it all together. Technorati: Gene Genie genes genetics disease blog carnival (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=500089 Sun, 25 Mar 2007 19:02:54 +0100 500089 http://sciencesque.wordpress.com/2007/03/23/random-omim-search-term-of-the-day-instance/ So, having been let down by the Random Word Genie yesterday, I mustered up some courage and again sought guidance in my journey though the human genome. The Genie revealed unto me that I shall search the OMIM database with the term “instance“. Thus instructed, let’s venture into the vast expanse of the human genome… Again, as with the previous search term “organizer”, the Genie has lead me into familiar territory. The word “instance” brings up not a gene, but rather a syndrome - PRADER-WILLI SYNDROME (PWS). The reason PWS is familiar to me is because Rachel Wevrick in the Department of Medical Genetics at the University of Alberta has centred her lab around genes associated with this disease. I have seen a number of excellent seminars from her and her students about their PWS research findings. PWS should also be familiar to clinical geneticists such as Berci at ScienceRoll, since it is a model for genomic imprinting diseases. Genomic imprinting Before getting into the nuts and bolts of Prader-Willi syndrome, I need to provide some background information on the epigenetic phenomenon known as genomic imprinting. Typically, everyone has two copies of each gene: one from their mother and one from their father. For the majority of genes, the maternal and paternal alleles are both expressed (transcribed into mRNA), and usually the loss of one allele can be compensated for by the remaining allele. However, this is not true in all cases. Sometimes, only one allele (either the maternal or paternal) is expressed, while the other is silenced. This is genomic imprinting. Whatsmore, imprinting is not a random event. For some imprinted genes, it is always the maternal copy that is expressed, while the paternal is silenced. For others, we observe expression of the paternal copy and suppression of the maternal. How and why this imprinting decision is made, maintained and passed on are all hot topics of research with important implications for developmental biology, human disease, cloning, and stem cell research. Prader-Willi and imprinting Now that we know something about genomic imprinting, we can start to look at Prader-Willi Syndrome and its causes. Many genes in the PWS critical region are known to be imprinted, some maternally and others paternally. PWS is a collection of phenotypes caused by a loss of at least 10 paternally-imprinted genes in the q11.2-q13 region of chromosome 15. This can occur via three different mechanisms (see Figure 1 below). First, there can be a deletion of the PWS critical region in the paternal gametes, thus no genetic contribution from the father for genes within this region. Secondly, PWS can occur as a result of maternal uniparental disomy, where the embryo receives two copies of the maternal chromosome and no copies of the paternal. Lastly, and most rarely, mutations that affect the DNA methylation patterns on the paternal chromosome can also lead to PWS. Genetically speaking, loss of the imprinted allele is equivalent to having no copies of that gene at all, since the other parental copy has been rendered irreversibly nonfunctional. With regards to the genes contained within the 15q11.2-q13 region, Prader-Willi results when the paternally-imprinted alleles are missing or not transcribed, while a lack of maternal alleles in this region causes Angelman syndrome (AS). The phenotypes of PWS and AS are quite distinct, highlighting the fact that genes in this region are differentially imprinted. For those who are interested, Nicholis and Knepper (Annu Rev Genomics Hum Genet 2: 153-75. 2001) have written an excellent review on the genomic organization and function of the PWS/AS critical region. Figure 1: Genetic mechanisms of PWS inheritance Prader-Willi phenotypes PWS patients have a broad spectrum of phenotypes at all stages of development, most of which have been described in exceptional detail. Please see the OMIM article and the links within if you’re interested in all of the associated phenotypes. Briefly, PWS infants have reduced activity and movement, hypogonadism and craniofacial abnormalities. The infants also have a decreased interest in food, a phenotype that is somewhat ironic given the uncontrollable hyperphagia that plagues PWS patients later on. Adults display mild mental retardation, emotional instability, poor motor skills, and possess a distinct set of physical characteristics including close-set eyes, downturned mouth and obesity (Figure 2). Figure 2: Physical characteristics of PWS patients Hyperphagia and Obesity Perhaps the most striking phenotype of PWS patients is their uncontrollable compulsion to overeat. Patients seem to lack the signal that tells the brain “Your hunger has been satisfied. Stop eating now!” PWS patients will eat themselves to death if given unlimited access to food. For this reason, obesity researchers have been very interested in genes within the PWS critical region as possible genetic candidates for understanding eating disorders in non-PWS patients. Unfortunately, none of the animal models used to study PWS have the hyperphagic phenotype. This, combined with the fact that none of the genes in the PWS critical region have an obvious connection to obesity or satiety, has hampered efforts to elucidate the molecular mechanisms underlying PWS hyperphagia. However, in 2002 David Cummings et al. (Nature Medicine 8: 643 - 644.) published their findings that ghrelin (GH) levels are elevated in the plasma of PWS patients. Ghrelin is a hormone that stimulates hunger and growth hormone secretion, and elevated levels of which could explain hyperphagia and obesity in PWS patients. However, the ghrelin gene does not lie within the PWS critical region, therefore Cummings et al. speculate that a gene within the critical region is responsible for regulating some aspect of ghrelin function. However, such a connection has yet to be established. To conclude, Prader-Willi syndrome is an exceedingly complex genetic imprinting disorder involving a wide array of phenotypes and multiple genes. I have only scratched the surface of the literature surrounding PWS, and haven’t even mentioned the large amount of research done on PWS critical region genes such as necdin and the bicistronic Snurf-Snrpn locus. I encourage anyone who is interested in imprinting and human disease to delve further into this disorder. Blogged with Flock Tags: Gene Genie, OMIM, disease, Prader-willi syndrome, PWS, Angelman syndrome, AS, genetics, genomic imprinting, paternal imprinting, maternal imprinting, hyperphagia, obesity, ghrelin, overeating (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=498767 Sat, 24 Mar 2007 17:26:17 +0100 498767 http://sciencesque.wordpress.com/2007/03/23/random-omim-search-term-of-the-day-instance/ So, having been let down by the Random Word Genie yesterday, I mustered up some courage and again sought guidance in my journey though the human genome. The Genie revealed unto me that I shall search the OMIM database with the term “instance“. Thus instructed, let’s venture into the vast expanse of the human genome… Again, as with the previous search term “organizer”, the Genie has lead me into familiar territory. The word “instance” brings up not a gene, but rather a syndrome - PRADER-WILLI SYNDROME (PWS). The reason PWS is familiar to me is because Rachel Wevrick in the Department of Medical Genetics at the University of Alberta has centred her lab around this very interesting disease. I have seen a number of excellent seminars from her and her students about their PWS research findings. PWS should also be familiar to clinical geneticists such as Berci at ScienceRoll, since it is a model for genomic imprinting diseases. Genomic imprinting Before getting into the nuts and bolts of Prader-Willi syndrome, I need to provide some background information on the epigenetic phenomenon known as genomic imprinting. Typically, everyone has two copies of each gene: one from their mother and one from their father. For the majority of genes, the maternal and paternal alleles are both expressed (transcribed into mRNA), and usually the loss of one allele can be compensated for by the remaining allele. However, this is not true in all cases. Sometimes, only one allele (either the maternal or paternal) is expressed, while the other is silenced. This is genomic imprinting. Whatsmore, imprinting is not a random event. For some imprinted genes, it is always the maternal copy that is expressed, while the paternal is silenced. For others, we observe expression of the paternal copy and suppression of the maternal. How and why this imprinting decision is made, maintained and passed on are all hot topics of research with important implications for developmental biology, human disease, cloning, and stem cell research. Prader-Willi and imprinting Now that we know something about genomic imprinting, we can start to look at Prader-Willi Syndrome and its causes. Many genes in the PWS critical region are known to be imprinted, some maternally and others paternally. PWS is a collection of phenotypes caused by a loss of at least 10 paternally-imprinted genes in the q11.2-q12 region of chromosome 15. This can occur via three different mechanisms (see Figure 1 below). First, there can be a deletion of the PWS critical region in the paternal gametes, thus no genetic contribution from the father for genes within this region. Secondly, PWS can occur as a result of maternal uniparental disomy, where the embryo receives two copies of the maternal chromosome and no copies of the paternal. Lastly, and most rarely, mutations that affect the DNA methylation patterns on the paternal chromosome can also lead to PWS. Genetically speaking, loss of the imprinted allele is equivalent to having no copies of that gene at all, since the other parental copy has been rendered irreversibly nonfunctional. With regards to the genes contained within the 15q11.2-q13 region, Prader-Willi results when the paternally-imprinted alleles are missing or not transcribed, while a lack of maternal alleles in this region causes Angelman syndrome (AS). The phenotypes of PWS and AS are quite distinct, highlighting the fact that genes in this region are differentially imprinted. For those who are interested, Nicholis and Knepper (Annu Rev Genomics Hum Genet 2: 153-75. 2001) have written an excellent review on the genomic organization and function of the PWS/AS critical region. Figure 1: Genetic mechanisms of PWS inheritance Prader-Willi phenotypes PWS patients have a broad spectrum of phenotypes at all stages of development, most of which have been described in exceptional detail. Please see the OMIM article and the links within if you’re interested in all of the associated phenotypes. Briefly, PWS infants have reduced activity and movement, hypogonadism and craniofacial abnormalities. The infants also have a decreased interest in food, a phenotype that is somewhat ironic given the uncontrollable hyperphagia that plagues PWS patients later on. Adults display mild mental retardation, emotional instability, poor motor skills, and possess a distinct set of physical characteristics including close-set eyes, downturned mouth and obesity (Figure 2). Figure 2: Physical characteristics of PWS patients Hyperphagia and Obesity Perhaps the most striking phenotype of PWS patients is their uncontrollable compulsion to overeat. Patients seem to lack the signal that tells the brain “Your hunger has been satisfied. Stop eating now!” PWS patients will eat themselves to death if given unlimited access to food. For this reason, obesity researchers have been very interested in genes within the PWS critical region as possible genetic candidates for understanding eating disorders in non-PWS patients. Unfortunately, none of the animal models used to study PWS have the hyperphagic phenotype. This, combined with the fact that none of the genes in the PWS critical region have an obvious connection to obesity or satiety, has hampered efforts to elucidate the molecular mechanisms underlying PWS hyperphagia. However, in 2002 David Cummings et al. (Nature Medicine 8: 643 - 644.) published their findings that ghrelin (GH) levels are elevated in the plasma of PWS patients. Ghrelin is a hormone that stimulates hunger and growth hormone secretion, and elevated levels of which could explain hyperphagia and obesity in PWS patients. However, the ghrelin gene does not lie within the PWS critical region, therefore Cummings et al. speculate that a gene within the critical region is responsible for regulating some aspect of ghrelin function. However, such a connection has yet to be established. To conclude, Prader-Willi syndrome is an exceedingly complex genetic imprinting disorder involving a wide array of phenotypes and multiple genes. I have only scratched the surface of the literature surrounding PWS, and haven’t even mentioned the large amount of research done on PWS critical region genes such as necdin and the bicistronic Snurf-Snrpn locus. I encourage anyone who is interested in imprinting and human disease to delve further into this disorder. Blogged with Flock Tags: GeneGenie, OMIM, disease, Prader-willi syndrome, PWS, Angelman syndrome, AS, genetics, genomic imprinting, paternal imprinting, maternal imprinting, hyperphagia, obesity, ghrelin, overeating (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=497762 Sat, 24 Mar 2007 05:23:24 +0100 497762 http://sciencesque.wordpress.com/2007/03/22/omim-random-search-term-of-the-day-beast/ Well, this is a first. The Random Word Genie has let me down. Wishing to continue my journey through the vast expanse of the human genome, I petitioned the Random Word Genie for inspiration, and was provided with the term “beast”. Upon searching the OMIM database with said term, I received the following feedback: The following term was not found: beast. See Details. No items found. Did you mean: breast (745 items) No, I didn’t mean “breast”, though that would have been fruitful, no doubt. Let’s try again… Blogged with Flock Tags: Random word generator, OMIM, Online Mendelian Inheritance in Man (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=490751 Thu, 22 Mar 2007 19:36:38 +0100 490751 http://sciencesque.wordpress.com/2007/03/20/bmc-t-shirts-dress-up-for-your-favourite-open-access-journal/ If you are a supporter of open-access publishing, or simply like to look like a huge nerd, BioMed Central has started selling T-shirts decorated with the logos of its open-access journals. There are many to choose from, and if I am to be honest, most of them are not all that attractive. However, a few of the journals have some really snappy logos that make me want to publish with them (or at least buy their shirt). Here are a few of my favourites: Blogged with Flock Tags: t-shirt, open access, BMC, BioMed Central, science, journals, clothing (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486318 Wed, 21 Mar 2007 04:44:27 +0100 486318 http://sciencesque.wordpress.com/2007/03/20/the-tories-focus-on/ The big news in Canada today is the release of the 2007 federal budget by the minority Conservative government. Of all the commentaries I’ve read so far, the most astute is the article by John Ibbitson of the Globe and Mail. After spending many years as the opposition watching the Liberal government be all things to all people, the Tories have moved “boldly” towards the centre of the political spectrum. As Ibbitson said: “The Liberals should sue for identity theft”. I’m sure the Grits are calling their lawyers right now. Unfortunately, while this very Liberal budget is big on spending for families (a recent consideration of mine) and the environment (it’s about time), it falls sadly short of Liberal spending levels for the research funding agencies CIHR and NSERC. The Tories’ plan for bolstering our Knowledge Advantage can be found here. Both CIHR and NSERC have received $37 million each in budget increases for the next year, but this is simply not enough to rectify the research funding crisis in Canada right now. With CIHR grant funding rates at 16%, plus slashed budgets for those lucky few that have been funded, $37 million dollars is a laughably anemic sum. Especially considering that CIHR had asked for $1 billion in extra funding to right the wrongs done to Canadian science. I expect many researchers who were’t funded in the last competition will find themselves disappointed (and under-funded) once again. Even though funding for basic research is clearly not a priority for the Conservatives, there budget is not all bad news for Canadian science. The budget includes a substantial increase to the Canada Graduate Scholarship program to support graduate students during their doctoral programs. The Canada Research Chair program, designed to attract top researchers to Canada, also saw a cash injection. The Tories have also earmarked $800 million for the post-secondary education system, as well as $105 million to support seven Centres of Excellence spread across Canada. While this is all fine and good, I can’t help but feel that without adequate funding for academic university labs, the Tories will fall sort on their goals to make Canada more attractive to foreign students and researchers. It is the equivalent of building a beautiful house, but not having any money left over to furnish it. Of course, this budget was a calculated move by the Tories to broaden their appeal and avoid having their minority government toppled. And it’ll probably work too, since the Liberals would look like hypocrites for not supporting a budget that they themselves could have drafted. Believe it or not, health and science research funding is not high on the list of priorities for the vast majority of Canadians, and for that reason was not a focus of this budget. For those of us who do care, we can only hope that next year, the Tories will focus less on vote-massaging and more on making the business of science in Canada healthy again.   Technorati: Canada, science, research, NSERC, CIHR, funding, federal budget, Jim Flaherty, Conservative government, Stephen Harper, education, Tories, Liberals, Grits (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486319 Tue, 20 Mar 2007 18:25:24 +0100 486319 http://sciencesque.wordpress.com/2007/03/19/whoo-hoo-im-a-daddy/ Last Tues, March 13 at 11:23 am, our baby daughter Sadie Adelaide Erickson was born. Without even a hint of exageration, Sadie’s birthday was the greatest day of my life. I am taken aback by how immediate and unbreakable my love for her is. My wife tells people that I have claimed her as all mine, and indeed I have. Now comes the time when Christine and I have to use that love as a source of strength during the 3 am feedings and crying sessions. Today is my first day back to school since the great event, and let me just say that I’m not running on all cylinders. Christine figures that our collective IQ has dropped precipitously since Sadie’s arrival. Too much baby talk like “oh, you’re sooooo cute, yes you are, my beautiful Sadie!” doesn’t exercise the brain muscle very well. Nor does a lack of sleep. When I arrived at the university this morning for my 3 hour Biology Resource Room shift, I was mortified to see three students lined-up outside the room waiting for help. I haven’t even come close to thinking about teaching, biology, or even science since last Tuesday, and my brain was not prepared for immediate onslaught of questions and poorly written essays. The final draft of their biology writing assignments are due this week, and I’m supposed to guide their literary minds towards compositional genius. I feel sorry for those poor students that decided to seek out help today. Hopefully, I strung together a few coherent sentences and choice pieces of advice. Official apology: Timothy Erickson deeply regrets if he is unable to improve the quality of your education. He hopes to sleep for more than 3 hours at a time at some point in the near future. (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486321 Mon, 19 Mar 2007 18:19:41 +0100 486321 http://sciencesque.wordpress.com/2007/03/12/caveat-lector/ Judging from these headlines, I can see why some people don’t know what to believe and are left with a mistrust of scientific research. Nov 5, 2004 - New brain cells develop during alcohol abstinence. April 27, 2005 - A little booze leads to new brain cells. Argh, I’m so confused!! Maybe the truth is simply that we get new brain cells! The apparent conflict between the two headlines can be easily dispelled by looking into how the experiments were actually performed. In the first article, the researchers turned the rats into chronic alcoholics, which leads to a loss of brain mass, cognitive impairment, and a decrease in hippocampal neurogenesis. Following their alcohol bringe, the rats got on the wagon, and it was determined that abstinence lead to increased cell division in the hippocampus. The authors conclude that this new round of neurogenesis is responsible for the return of some cognitive abilities during abstinence following chronic alcohol abuse in humans. In the second article, moderate amounts of alcohol were given to mice over a long period of time, and the amount of cell proliferation in the hippocampus was found to have increased compared to the control group. However, after three days of abstinence, neurogenesis returned to basal levels. So, even though these two headlines appear to send mixed messages, they are really saying that sustained moderate alcohol consumption could stimulate new cell formation in the hippocampus, but that abstinence will only help you after you’ve already drunk yourself into brain (and liver) damage. While I’m all for the dissemination of scientific research findings to the general public, our news ticker headline culture leaves out all of the nuances that could resolve what appears to be conflicting results. And unfortunately, to attract readers, it takes a headline that’s big on style and light on substance (just read any headline on Digg). If a reader isn’t inclined to venture past the headline, they might well be left with the wrong idea concerning the actual content of a story, or the significance of a study or clinical trial. Given the complexities and subtleties of scientific research, I believe oversimplification to be more of a concern when communicating science than it is for other areas of interest to the public. Neither headline here is grossly inaccurate, although Headline #1 does omit chronic alcoholism as a prerequisite for new neuron formation. And when juxaposed, they beg the reader to delve further into the subject matter. The real problem arises when misleading or incomplete headlines don’t have a foil that sets off the alarm bells. Perhaps popular science articles should come with warning labels - “Reader beware: catchy headline may not be entirely accurate. Please read beyond the headline for more information.” UPDATE: After finishing this post, I was reading Pharyngula, where I came across a statement by famed scientist and author, Lynn Margulis. I can safely say that her book, Microcosmos, changed the way I looked at biology. Early in my science education, it cemented the idea that all life is woven together by multiple threads. Dr. Margulis’ statement addresses how science is communicated, and I reproduce part of that statement here. It sums up what I was trying to say with a clarity and elegance that I could only hope to achieve. “Although misunderstanding permeates all human communication, the internet amplifies these tendencies. Sound bite-hype is far more useful to those who assert religious truths and would banish authentic science from the public sphere than to the scholar or scientist. Science itself, and even more so, science writing, ever cautious, ever tentative and ever questioning is permeated with boring hesitancies and stuttering qualifications. Most readers simply ignore it since they find it incomprehensible. The more accurate the scientific description, the more daunting the language to any outsider. The more clear the expression of a scientific idea is, the more specialized the terminology. The clearest scientific ideas are mathematical equations opaque to all but the specialist. So, when reporters and popular writers attempt to communicate real science the plagues of distortion, misunderstanding and misrepresentation are inevitable. Any statement outside the immediate purview of the detailed science tends to be “translated” into common language. To express new ideas that challenge the paradigm in which the scientist works new language is required. If the language is too new neither the scientist nor the science popularizer is understood. Especially when one’s work is heterodox to the prevailing trend -it is easy to be dismissed as a “crank” or “on the fringe.” Or, even more likely, to be ignored. The convenient fiction, created by marketers and politicians, that “consensus” plays a major role in original science, helps to generate confusion in the lay public about the vast difference between established scientific fact and ideologically-driven nonsense.” UPDATE 2: Bioephemera has a nice discussion on the lack of linguistic consistency in science writing. Cleverly, she links this back to the lack of consistency in the genetic code. Very nice!   Technorati: science, neuroscience, biology, alcohol, rat, mouse, hippocampus, alcoholism, brain (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486322 Mon, 12 Mar 2007 23:05:52 +0100 486322 http://sciencesque.wordpress.com/2007/03/12/big-changes-are-on-the-way/ Sciencesque has been sadly neglected over the past week, but all for a good cause. My wife and I are expecting our first child, and we’ve been running around in a mad rush to get everything done before the great arrival. She is due tomorrow, but the early labour contractions have begun this morning, so things are looking good. Yippeeee!!! Plus, we got a new kitty last week - a nice boy we’ve named Oliver. Even though we miss our old kitty Blue very much, we felt that we have too much love not to save another kitty and have him live with us. Oliver has a completely different personality than Blue, and demands that we play with him all the time. So, between the baby and Oliver, we’ll have our work cut out for us. Future blog posts might be about sleep deprivation, and / or might simply be completely incoherent. > (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486323 Mon, 12 Mar 2007 17:00:54 +0100 486323 http://sciencesque.wordpress.com/2007/03/04/dont-cheat-your-way-to-a-university-degree-because-youll-get-screwed/ About three weeks ago, I wrote about an article in McLeans in which they claimed over 50% of university students are cheating their way through their degrees. Of course, this news sent shock waves through the Canadian education system since the findings essentially devalue everyone’s university degree. However, not everyone agrees with the McLeans article, and on March 1st, another point of view was published in the U of A student paper The Gateway. The Gateway article questions how McLeans weighted their survey data. When McLeans says that over 50% of students cheat, they are lumping together activities such as cheating on final exams and plagerizing term papers with other milder infractions such as asking a friend for the answer to Question 3 on your Organic Chem pre-lab assignment. Now, while it is dangerous to start defining different levels of “wrongness” for cheating, hardly anyone could seriously argue that university degrees are worthless because of the collaborative study efforts that many students engage in. In fact, I would argue that the University already acknowledges that some forms of cheating are less wrong than others. The grading structure in most classes is such that assignments where students could readily collaborate are not worth many marks. Likewise, the punishments handed out to students who are caught cheating on lesser assignments are milder than those for major lapses in judgement. The ethical implications for all forms of cheating may be the same, but the benefits to the cheater are not equivalent, nor is the harm done to non-cheating students. I can see why Mcleans presented their story in the way they did. First of all, it makes for better reading, creates publicity, and sells more magazines. Secondly, I’m sure that Mcleans did not want to start defining which forms of cheating were worse than others. If they had done so, we would have heard vehement protests from every university across the country. The other interesting point brought up in the Gateway article comes from Deborah Eerkes, the acting director in the Office of Student Judicial Affairs at the University of Alberta: “One of the big motivators for cheating would be that students think everyone else is cheating,” Eerkes explained. “And so these statistics, which are somewhat misleading—50 per cent of students cheat—just perpetuates the problem. Students think, ‘Oh everyone’s cheating, I have to too.’” Let’s hope that McLeans’ quest to sell magazines doesn’t lead to a followup article in a few years showing a huge spike in cheating offences following the first article. I also have an update on the student I caught cheating on her final exam last term. The original decision by the department was a 0% on the final, and a disciplinary fail (F8) for the class. The student appealed that decision, and it was agreed that the issue would be brought in front of a Student Appeal Court for a final and binding ruling. The structure of the appeal court was as follows: [1] an appeal board consisting of two students (one grad, one undergrad I believe), and a member of the academic faculty, [2] The Appellant (the student and her ombudsman advisor, and [3] the Respondents, which presented the case for the department. I was called as the first witness for the Respondents. There were no other witnesses in the room during my questioning, and I wasn’t allowed to watch the testimony of the subsequent witnesses. The situation was quite non-confrontational, and I was asked a simple series of questions about the events as I remembered them. Everyone in the room had the opportunity to ask me a question, and almost everyone did, except for the student herself. In theory, the student’s advisor isn’t supposed to ask questions, but should merely direct the student in their line of questioning. However, since she wasn’t feeling up to defending herself, her advisor did all of the talking. The questioning probably lasted 15-20 minutes, and then I was free to go. As I mentioned before, both parties agreed beforehand that the decision of the Student Appeal Board would be final and binding. The Board had the power to remove, reduce, uphold, or increase the initial punishment handed out by the department. While no one was expecting the Board to throw the whole incident out entirely, there was some precedent to suggest that they may lessen the punishment. However, I was surprised (perhaps pleased?) to hear that the Board not only upheld the initial punishment, but also tacked on a 4-month suspension! Ouch, that’s gottah hurt! You know kids, there is something to be said for taking responsibility for your actions. If you keep on blaming other people, or the circumstances surrounding the incident, sometimes you’re just going to make things worse. Is this “get tough” stance on cheating a direct result of the McLeans article? Could be. If so, then even though the article might be a bit sensationalized, McLeans has done a great job in giving the universities a good kick in the seat of the pants. Kudos to McLeans for bring this epidemic to light, and three cheers to the University of Alberta for not wimping out.   Technorati: cheating university degree McLeans (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486324 Sun, 04 Mar 2007 17:56:51 +0100 486324 http://sciencesque.wordpress.com/2007/03/03/the-genotype-of-sciencesque/ Via ScienceRoll, I came across Web2DNA, a project that uses a number of parameters to “genotype” your website. It then produces a stylized DNA gel like this one: I think what this is telling me is that I need to get hip to HTML and I use too much text. Maybe I should use more graphs and flowcharts…   Technorati: web2DNA, art, html, websites (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486325 Sat, 03 Mar 2007 22:24:29 +0100 486325 http://sciencesque.wordpress.com/2007/03/03/the-gene-genie-issue-2/ Just ahead in this issue of the Gene Genie - Gum disease: it’s not just a matter of bad hygiene anymore! Next, find out the genetic basis for why you or someone you love falls off bicycles and can’t solve puzzles. Also in this issue, unlock the secrets of human genetic variation, and read about the challenges of living with a rare genetic disorder called Pompe Disease. Learn about two chilling examples of what happens when stop codons attack our genes! Also, join the Random Word genie for an exciting plunge into the human genome. And lastly, we take a very “serious” look at the quest to unravel the God genome. We’ll begin this issue of the Gene Genie with two articles from Berci Mesko at ScienceRoll. Near the beginning of February, Berci wrote an article on Pompe disease, a rare but serious glyogen storage disorder caused by a deficiency in the acid alpha-glucosidase enzyme. For this issue of the Gene Genie, Berci interviewed a fellow blogger named Juan Magdaraog who actually has Pompe disease. In the interview, Juan highlights some of the challenges he faces living with the disease, and also provides some insight into how treatment of his condition is progressing. In his second article, Berci tells us about the ongoing Human Variome Project (HVP). One of the problems Juan faced early on in his disease was misdiagnosis. One of the goals of the HVP is to aid physicians and patients in making more rapid and accurate diagnoses so that treatment can begin earlier and be more effective. And in the “Everything has a genetic explanation” department, the Gene Genie presents articles from Thomas Yoon (Your Oral Health) and Hsien-Hsien Lei (Genetics & Health). First off, Thomas talks about a possible genetic basis for aggressive periodontal (gum) disease. This form of gum disease is different from the milder form you can get from not brushing and flossing regularily. Thomas points out that aggressive periodontitis is a phenotype of several genetics disorders, and then discusses some of the genes that may be involved in susceptibility to gum disease. For her submission, Hsien-Hsien Lei puts a comical spin on a recent finding that the CHRM2 gene is linked to performance on IQ tests. CHRM2 codes for a cholinerginc receptor protein, defects in which may explain some of the problems that Dr. Lei experiences in her day-to-day life ;^) Larry Moran at Sandwalk explores two examples of what can happen when a gene acquires a premature stop codon and produces a truncated protein. Often, mutations that result in non-functional proteins are selected against and would not become established in a population. However, for various reasons (genetic bottleneck, obvious or non-obvious advantages in reproductive success), there are instances where “broken” genes pass the natural selection acid test and become widespread in a population. Larry explores this concept using the ABO gene and GULOP pseudogene as examples. The various alleles of the ABO (N-acetylgalactosaminyltransferase) gene are responsible for the A, B, and O blood groups in the human population. Larry describes the specific DNA sequence variation in the ABO gene that leads to the O blood group. In the second submission, Larry provides some evolutionary history of the GULOP (L-glucono-γ-lactone oxidase) gene. If it weren’t for this pseudogene, we wouldn’t refer to British sailors as “limies”. My own contribution to this issue comes courtesy of the Random Word generator than I use to provide me with OMIM search terms for a non-directed meander through the human genome. My last search term was “organizer”, and this lead me to investigate the GBX2 gene. The GBX2 protein is a homeodomain transcription factor that regulates gene expression during early embryonic development. Using animal models (mouse, chick, zebrafish, amphioxus), it has been shown that GBX2 plays a crucial role in neural patterning, especially with regards to the midbrain. We’ll end on a humourous note with a submission from Avant News. It has recently come to light that a tomb found near Jerusalem in 1980 may actually contain the bodies of Jesus, his wife and family. Film director James Cameron, who has made a documentary film about the archeological finding, claims that there is conclusive DNA evidence to support the idea that the bodies in the tomb really are those of Jesus and his family. It is beyond me how Cameron figures that DNA sequencing can confirm that this is the Jesus who many claim is the Son of God. However, if that is the body of Jesus Christ in the tomb, Avant News provides us with the formula to determine the sequence God’s DNA itself. Furthermore, the article contains a surprising phylogenetic analysis, and proposes a few useful things we could learn from sequencing the genome of an all-powerful being. Thank you Avant News for using humour to point out some of the craziness surrounding this recent news story. Thus ends the second issue of the Gene Genie. Thanks to everyone who participated. If you have a favourite gene or disease and want the world to hear about it, please submit an article for inclusion in the next issue. Also, if anyone is interested in hosting the next issue (or one in the near future), please contact ScienceRoll at berci.mesko@axelero.hu.   Technorati: Gene Genie, Blog Carnival, genes, genetics, disease, human genome, Pompe disease, human variome, gum disease, periodontitis, CHRM2, IQ, ABO, blood groups, scurvy, vitamin C, pseudogene, developmental biology, GBX2, midbrain, James Cameron, Jesus, God, tomb (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486326 Sat, 03 Mar 2007 21:51:35 +0100 486326 http://sciencesque.wordpress.com/2007/02/27/a-history-of-morpholinos/ In response to my blog entry about my lab’s use of morpholinos to characterize gdf6a function in zebrafish eye patterning, Jon Moulton of Gene Tools has posted a brief history of the morpholino. He gently corrects my statement that morpholino technology is 10 years old, and points out the Jim Summerton originally tried to publish his ideas about antisense gene silencing back in 1973, but the paper was rejected on the grounds that it was a “pipe dream”. Eventually, the paper was published in 1979. Morpholinos were made commercially available in 2000, with the first demonstration of their usefulness in zebrafish being published that same year. Of course, I was aware of the zebrafish timeline, but was a little fuzzy on the early years of the morpholino. I’ve corrected my statement in my original blog entry to reflect this information. Thanks for the history lesson Jon!   Technorati: morpholino, history of science, zebrafish, antisense, gene silencing (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486327 Tue, 27 Feb 2007 20:33:54 +0100 486327 http://sciencesque.wordpress.com/2007/02/26/im-this-kind-of-parasite/ I’m glad I’m human, since I wouldn’t like myself as a parasite very much. I’d always hoped I’d be a way cooler parasite, not one that makes pretty. Maybe one that controls the behaviour of its host! From Scan Man.   Technorati: quiz, parasite, eyelash, mite (Source: Sciencesque) Sciencesque blogs http://www.medworm.com/rss/comments.php?id=486328 Tue, 27 Feb 2007 05:11:28 +0100 486328