MedWorm Tags: chromosome

Acute Myelogenous Leukemia (AML)

Inside Surgery — Mon, 25 Apr 2011 06:00:43 +0100

Pathophysiology group of disorders (at least nine different variants) in which a hematopoietic stem cell becomes neoplastic or alternately an individual lineage of stem cells (e.g., erythrocytes, monocytes, granulocytes, or megakaryocytes) becomes neoplastic Signs and Symptoms 1) usually presents with signs of anemia – pallor, fatigue, weakness 2) splenomegaly 3) hepatomegaly 4) hemorrhage in GI tract and CNS if platelets are < 20,000/dL 5) dyspnea owing to infiltration of lung by leukocytes 6) secondary infections 7) gingival hyperplasia Characteristic Test Findings Bone marrow – 1) by definition, > 30% of nucleated cells are blasts Laboratory – 2) anemia 3) thrombocytopenia 4) neutrophilia (but total leukocyte count may be increased or decreased) Histology/Gross Patholo...

I, Too, Have a Dream — About Mental Health

World of Psychology — Mon, 17 Jan 2011 14:15:06 +0100

Some of you may recognize my dream, but I like to repost it every now and then to keep it alive and give it legs. In celebration of Martin Luther King, Jr.: I have a dream that one day I won’t hold my breath every time I tell a person that I suffer from bipolar disorder, that I won’t feel shameful in confessing my mental illness. I have a dream that people won’t feel the need to applaud me for my courage on writing and speaking publicly about my disease, because the diagnosis of depression and bipolar disorder would be understood no differently than that of diabetes, arthritis, or dementia. I have a dream that the research into genetics of mood disorders will continue to pinpoint specific genes that may predispose individuals and families to depression and bipolar disord...

ADHD: Is It Genetic?

Better Health — Sat, 02 Oct 2010 19:00:00 +0100

British scientists announced that attention-deficit/hyperactivity disorder (ADHD) has been linked to deleted or duplicated DNA segments (copy number variants), which leads to developmental difference in the brains of children with the condition. Researchers scanned genomes of 366 children with ADHD and compared them with 1,047 unrelated, ethnically matched control subjects. They reported full results in The Lancet. Rare copy number variants were almost twice as common in children with ADHD compared to the other children. Researchers commented to Reuters that there was a significant overlap between copy number variants found in ADHD and elements of the genome linked to autism and schizophrenia, specifically in a region on chromosome 16. *This blog post was originally published at AC...

Alagille’s Syndrome (Arteriohepatic Disease)

Inside Surgery — Wed, 07 Jul 2010 14:50:06 +0100

Pathophysiology infantile intrahepatic cholestasis owing to an interstitial gene deletion on chromosome 20 Signs and Symptoms 1) broad forehead 2) deep-set eyes 3) bulbous nose 4) butterfly vertebrae 5) pulmonic stenosis Histology/Gross Pathology paucity of intrahepatic bile ducts Inheritance/Epidemiology 1) both autosomal dominant and sporadic cases are reported 2) occurs in 1/70,000 3) deletion is on chromosome 20 (p11.23) Treatment Liver transplantation Tips for USMLE If question mentions infant with increased bilirubin, must consider Alagille’s, Gilbert’s, Crigler-Najjar, and Dubin’s syndromes (Source: Inside Surgery)

UCL Scientists Discover How To Switch On Critical Ovarian Cancer “Protector” Gene & Arrest Tumor Growth

Libby's H*O*P*E* — Tue, 06 Jul 2010 06:58:27 +0100

A new University College London study reveals that a gene [EPB41L3] which normally protects against ovarian cancer is switched off in 66% of ovarian cancer cases and switching it back on arrests tumor growth. A new University College London study reveals that a gene which normally protects against ovarian cancer is switched off in 66% [...] (Source: Libby's H*O*P*E*)

On the Path to Early Detection: Fox Chase & Sloan-Kettering Researchers Identify Early Ovarian Cancers

Libby's H*O*P*E* — Tue, 27 Apr 2010 04:01:54 +0100

Researchers at the Fox Chase Cancer Center and the Memorial Sloan-Kettering Cancer Center discover early tumors and precancerous lesions in cysts that fold into the ovary from its surface, called inclusion cysts. “This is the first study giving very strong evidence that a substantial number of ovarian cancers arise in inclusion cysts and that there [...] (Source: Libby's H*O*P*E*)

Ewing’s Sarcoma

Inside Surgery — Thu, 18 Feb 2010 02:01:53 +0100

Pathophysiology 1) aggressive type of bone neoplasm affecting mostly adolescents 2) considered a type of primitive neuroectodermal tumor of childhood, even though the original neoplastic transformation is probably mesenchymal in origin (possibly in the bone marrow) 3) also occurs in soft tissue 4) 90% of cases associated with the 11/22 chromosome translocation Signs and Symptoms 1) pain at affected site 2) adjacent soft tissue mass 3) fever 4) most commonly affects long bones (especially humerus, tibia, and femur) 5) metastases are via blood system and go to lungs (most commonly), other bones, and bone marrow 6) patients sometimes give history of mass and pain arising after area has received a trauma Characteristic Test Findings Laboratory – 1) leukocytosis Radiology – 2) class...

Bornavirus DNA in the mammalian genome

virology blog — Wed, 13 Jan 2010 15:22:03 +0100

The chromosomal DNA of several mammals has been found to contain sequences related to the nucleoprotein (N) gene of bornaviruses, enveloped viruses with a negative-strand RNA genome. I am amazed by this finding. How did bornaviral DNA get in our chromosomes, and what is it doing there? A search of the human genome sequence revealed DNA copies of the bornaviral N protein gene. This 370 amino acid viral protein is wrapped around the viral RNA, where it functions during RNA synthesis. Four different insertions of N protein DNA were found, all encoding proteins that are shorter than the viral counterpart. DNA encoding bornaviral N protein was also found in the genomes of the chimpanzee, gorilla, orangutan, rhesus macaque, lemur, Garnett’s galago, African elephant, Cape hyrax, rat, mou...

When Rare Chromosome Disorders Occur

Genetics and Health — Thu, 01 Oct 2009 03:59:26 +0100

The normal human karyotype has two sets of chromosomes, one set inherited from each parent, so that we have 46 chromosomes (22 pairs, including either an XX if you’re a female, or XY if male). But sometimes during cell division of the zygote (early in fertilization), the chromosomes don’t divide properly into their respective cells and the developing fetus carries an abnormal number of chromosomes in all cells of the body (termed aneuploidy). Usually the fetus does not survive into full term, but in some cases when the baby does, a rare chromosome disorder happens. Trisomy happens when there are three copies of a chromosome, instead of the normal two copies. Take for example Down Syndrome, which is caused by an extra copy of chromosome 21, resulting in 47 chromosomes. Every pe...

It All Begins With the Chromosome

Genetics and Health — Fri, 25 Sep 2009 04:39:47 +0100

For many of us, GENETICS is a intimidating topic. Don’t worry, I feel the same way around technology and computer language. When we start reading sentences where half the words are foreign, then it can seem way over our heads. And I think people have an idea that genetics is important to medicine and health care, but what role it plays (and how genes act) might be where the questions are. So that’s why I’m adding a regular feature to explain the basics and call it “What we need to know to get genetics” or something like that. Obviously, this won’t be the “complete course in Genetics 101” or “Genetics for Dummies” (there’s a already a Genetics For Dummies (For Dummies (Math & Science))’ target=_blank>book on that) but hopefully the outlines below would be...

New Genetic Variants Linked with Risk of Prostate Cancer

psa-rising.com/blog — Mon, 21 Sep 2009 20:33:15 +0100

Scientists have identified seven new genetic variants that appear to be linked with increase risk of prostate cancer. Among these are four new “single-letter” genetic variants on one particular chromosome, called 8q24. This chromosomal region has previously been associated with breast, colon, and bladder cancer. The discoveries identifying the four new genetic [...] (Source: psa-rising.com/blog)

Beyond BRCA1 & BRCA2: U.K. Researchers Identify Genetic Defect That Could Increase Risk of Ovarian Cancer Up To 40%

Libby's H*O*P*E* — Mon, 03 Aug 2009 21:59:29 +0100

Scientists have located a region of DNA which – when altered – can increase the risk of ovarian cancer according to research published in Nature Genetics today. An international research group led by scientists based at the Cancer Research UK Genetic Epidemiology Unit, at the University of Cambridge and UCL (University College London) searched [...] (Source: Libby's H*O*P*E*)

New Study Shows Four-Year Window for Early Detection of Ovarian Cancer

Libby's H*O*P*E* — Sat, 01 Aug 2009 22:45:36 +0100

A new study by Howard Hughes Medical Institute researchers shows that most early stage ovarian tumors exist for years at a size that is a thousand times smaller than existing tests can detect reliably. But the researchers say their findings also point to new opportunities for detecting ovarian cancer—a roughly four-year window during which most [...] (Source: Libby's H*O*P*E*)

Cub’s Pitcher Deals With Daughter’s Disorder

Genetics and Health — Tue, 21 Jul 2009 21:08:00 +0100

What do you know when life hits you with a curve ball? Chicago Cub pitcher Ryan Dempster knows how to throw one in the field. And in real life, he is fighting hard as life hits his family with a curve ball. Dempster’s newborn daughter Riley has been diagnosed with DiGeorge Syndrome, a genetic disorder with very little resource around it. DiGeorge Syndrome is a congenital disorder caused by deletions in large portions of chromosome 22, resulting in the loss of several genes. The most common characteristic is an absent or nonfunctional thymus. The thymus is involved in producing mature immune cells, so persons with DGS are vulnerable to infections. However, the literatures also mention at least 45 genes are in this region, and as many as 186 symptoms associated with it, so there is also...

Breakthrough for Schizophrenia and Bipolar

World of Psychology — Thu, 02 Jul 2009 19:00:34 +0100

Earlier today, we reported that NIMH-funded researchers at three different genetic research institutes from around the world collaborated and published three new studies yesterday in the journal, Nature, that suggested a true breakthrough in our understanding of schizophrenia and bipolar disorder. And to think that just earlier this week, I was dismissing the largely inconclusive findings of genetics research in mental illness. One of the researchers commented on the findings: “There was substantial overlap in the genetic risk for schizophrenia and bipolar disorder that was specific to mental disorders. We saw no association between the suspect gene variants and half a dozen common non-psychiatric disorders.” This is an important discovery — that some of the roots of schi...

Universal Prenatal Test to ID 15K Genetic Conditions

Genetics and Health — Wed, 01 Jul 2009 07:34:17 +0100

Will a new prenatal genetic test create designer babies? That’s one of the questions raised as news that a universal embryo test could be available next year. The current method for prenatal genetic testing involves either amniocentesis or chorionic villus sampling (CVS) to get embryo fluids or placenta cells from a pregnant woman’s abdomen. The placenta or placental fluids contain cells generated by the fetus. These cells are used to identify chromosomal abnormalities that can affect a baby’s survival or capacity at birth. Prenatal genetic tests are mainly used to provide information to the parents about their unborn child’s genetic condition before birth, so they can make informed decisions and manage the pregnancy better. Unfortunately, the current methods are invasive and te...

Dad’s sperms have role in embryo development

Genetics and Health — Sun, 21 Jun 2009 03:01:00 +0100

The elementary concept is that the father’s role in making babies is to only contribute the sperm, and the mother does all the work. That after fertilization, the development of the resulting embryo is at the mercy of the mother’s egg cytoplasm that received it. Well, recent studies show that dad’s sperm contains a set of instructions that make certain the embryo develops properly, and specifically that his genes get turned on at the right time. But let’s do a short tutorial first… Each chromosome is really just a single long DNA molecule, that can stretch out to an average 1 meter long. Those 23 long strands of human DNA must be packaged and coiled into a tiny nucleus. The proteins responsible for packaging them are called histones. Histone molecules repeatedly fold and coil...

Have gum disease? Beware of heart attack

Genetics and Health — Fri, 29 May 2009 22:43:00 +0100

Did you know that having gum disease (periodontitis) is a risk factor for cardiovascular diseases (CVD)? It’s been found that people with periodontal diseases are twice as likely to get coronary artery disease than those without any gum disease. Almost 92% of people who have CVD also have severe to moderate periodontitis, according to a 2004 study. Some studies suggest that oral bacteria can enter the bloodstream and contribute to a thickening of the arterial walls or clot formation. Any blockage of the arteries can lead to heart attacks. But a new study found that gum and heart disease may actually share the same variation of a gene! The researchers found that a locus on chromosome 9p21. is associated with both heart attack and gum disease. Both diseases share several risk factors in...

Genetics and Health Showroom for your holiday gift ideas

Genetics and Health — Fri, 28 Nov 2008 15:59:49 +0100

The day after Thanksgiving is the most important holiday before Christmas. It’s our signal to start shopping for holiday gifts! But what do you give someone who is crazy about genetics? Well, my friend, you came to the right store, if you need a gift for any of the following reasons: The holidays! What better way to say Merry XX-Mas! (or Merry XY-Mas!) Birthdays and anniversaries, graduate fellowships, employment, promotions, new discoveries, grant approval, postdoctoral work and all the major accomplishments in life! Something for your boss; your boss’ boss; your professor; your department head and all the important people who can sign your papers! Something for your laboratory head, technicians, the statisticians and programmers, and everyone who makes your life easier. Someth...

A “protective” gene?

Autism Vox — Fri, 14 Nov 2008 21:09:09 +0100

Grace at Genetics and Health posts about research on regions of DNA that may increase the risk to hereditary autism (from Craegmoor Healthcare). The findings were reported on at the 58th Annual Meeting of the American Society of Human Genetics meeting in Philadelphia: According to the Scientist, a large-effect allele that provides protection against autism was found on chromosome 5 near the semaphorin 5A (SEMA5A) gene, which is involved in guiding neural axons during development. The same group also found two genes not previously linked to autism, one at the tip of chromosome 20’s short arm, and one at the end of chromosome 6’s long arm. The findings were reported by Dan Arking, Assistant Professor in the McKusick-Nathans Institute of Genetic Medicine at Johns Hopkins University School...

Breaking news! Baldness genes come from dad too

Genetics and Health — Tue, 14 Oct 2008 03:39:48 +0100

The gene for male-pattern baldness (androgen receptor) has traditionally been linked to the X chromosome which means mom passes it on to her sons. Now, two new independent studies published yesterday at the Nature Genetics identified association between hair loss and chromosome 20. A genome-wide association study (GWAS) for male-pattern baldness, or androgenetic alopecia, identified a new association at chromosome 20p11.22, between the PAX1 and FOXA2 genes, and confirmed a previous association with the gene encoding the androgen receptor in the X. Tim Spector and colleagues found that 1 in 7 men carry both the chromosome X and chromosome 20 variants, and that these men have a 7-fold risk of having pattern baldness. Another independent GWAS found overwhelming evidence for five SNPs on chr...

New test for Down Syndrome - safer than amniocentesis

Genetics and Health — Tue, 07 Oct 2008 08:08:23 +0100

There was one compelling reason why I opted out of genetic testing with my last pregnancy. The risk of miscarriage due to amniocentesis was the same as the risk of having a baby with Down Syndrome. Amniocentesis is considered the gold standard, but it’s an invasive procedure with a 1/100 risk for miscarriage, the same risk for Downs. I quickly realized I would rather give birth to a baby with Downs than be responsible for a miscarriage. Fortunately, now there is a new, totally non-invasive procedure for genetic testing of Down Syndrome. It only requires the maternal blood sample (basic blood draw) to spot chromosomal abnormalities in the fetus. Scientists from Stanford University utilized fetal DNA fragments in the mother’s blood and read the fragments using DNA sequencing. Wom...

Egyptian pharoah Akhenaten’s feminine appearance suggest gene defects

Genetics and Health — Sat, 24 May 2008 12:00:08 +0100

King Akhenaten (photo credit www.usu.edu) The feminine features and elongated head of ancient Egypt’s King Akhenaten may be attributed to two genetic defects called aromatose excess syndrome and craniosynostosis, reports Yale School of Medicine dermatology Professor Irwin Braverman, M.D. Akhenaten, a pharaoh during Egypt’s 18th Dynasty credited with starting the practice of worshipping one God, fathered six children. He was often portrayed in sculptures and carvings with a thin neck, elongated head, large buttocks, breasts, and even a prominent belly, suggesting pregnancy. Aromatose excess syndrome can lead to feminine features in men and advanced sexual development in girls. Akhenaten’s daughters are depicted with breasts at age three and seven in some carvings. It ma...

Leukemia - risk of which patients could relapse, identified

Genetics and Health — Sun, 04 May 2008 08:26:48 +0100

(Photo courtesy www.leukemia101.com) Researchers at the Ohio State University Comprehensive Cancer Center may have discovered a better way to distinguish acute leukemia patients who require aggressive treatment to prevent recurrence from those who need only standard therapy for cure. About 13,300 new cases of AML and 8,200 deaths from the disease are expected this year in the United States. In about half of cases, patients’ leukemia cells have chromosome changes that help doctors determine whether standard therapy will suffice to prevent recurrence, or whether the individual needs aggressive treatment such as a stem-cell transplant or an experimental therapy. The remaining patients have leukemia cells with chromosomes that look normal. Determining the best therapy for these individ...

Genetic breakthrough for migraine sufferers

Genetics and Health — Sun, 20 Apr 2008 20:05:46 +0100

MRI of a migraine Migraine is the most common cause of episodic headache, and by far the most common neurological cause of a doctor’s visit. It affects some 15% of the world’s population. Researchers from Helsinki University, Finland and the Sanger Institute, UK were able for the first time to convincingly demonstrate a genomic locus to be linked to migraine susceptibility in two diverse populations - 1700 patients from 210 Finnish and Australian families. This is especially interesting as Finnish and Australian populations are genetically distant. It also tied together previous research, resulting in very robust evidence for pinpointing the susceptibility region. Researchers identified one gene locus on chromosome 10q23, which showed significant evidence of genetic l...

Smokers and ex-smokers - lung cancer gene identified

Genetics and Health — Fri, 04 Apr 2008 14:18:29 +0100

A research team comprising scientists from MD Anderson, Johns Hopkins University and the Insitutute for Cancer Research and the University of Cambridge, UK have identified two inherited genetic variations (SNPs) on chromosome 15 associated with increased risk of lung cancer for smokers and former smokers. Individuals who have ever smoked and who have one or two copies of either of these SNPs have increased risks ranging from 28% to 81% of developing lung cancer. The findings are a major step forward in identifying those at high risk for non-small cell lung cancer and for understanding how smoking and genetic factors interact to cause the disease. The team’s findings might also provide support for a growing body of evidence suggesting that nicotine, long known as the prime addictive c...

The Genetics of Cigarettes

Addiction Inbox — Fri, 04 Apr 2008 02:45:00 +0100

Mutations on chromosome 15 linked to lung cancer A variation among the genes that code for nicotine receptors in the brain has been linked with increased cigarette smoking and a heightened risk for lung cancer, according to three new studies released this week.Two studies in Nature, and one in Nature Genetics, demonstrated that people who inherited the genetic variation, or allele, from one parent—roughly 50 percent of the population--had a 30 percent higher risk of developing lung cancer. “What’s more,” according to Michael Hopkin at Nature News, “another 10 percent of the population is likely to carry two copies of this set of mutations, raising cancer risk by as much as 80 percent relative to people with equivalent lifestyles without the cancer-linked gene variant.”More than...

‘Out of Africa’ - 3 studies trace human global migration

Genetics and Health — Sun, 24 Feb 2008 11:59:34 +0100

This study was based on the analysis of more than 500,000 SNPs and nearly 400 copy number variants — sections of DNA that are repeated or duplicated in the genome — for 485 individuals. These samples, representing individuals from 29 different populations around the world, were obtained as part of the Human Genome Diversity Project. The results suggest East Africans are the most genetically diverse, while Native American genomes exhibit the lowest genetic diversity. Middle Eastern, Asian, and European populations, on the other hand, fall somewhere in between. By following this decline in diversity, the Michigan team was able to retrace global human migration patterns. Consistent with previous archaeological date, language studies, and smaller genetic studies of mitochondrial DNA or a...

“My Aspartame Experiment” by Victoria Inness-Brown

Genetics and Health — Sun, 24 Feb 2008 11:59:12 +0100

Molecular structure of Aspartame I recently wrote an article on my first hand research experience on the potential carcinogenicity of Aspartame - the artificial sweetener used in thousands of everyday products, particularly diet products. It was titled “Aspartame is safe … really!” One of www.geneticsandhealth.com readers author Carol Guilford sent me the following interesting link to a piece of research on aspartame carried out by scientist Victoria Inness-Brown. I cannot comment on the science behind Victoria’s study as I have not investigated it. However, the results are quite thought provoking. Here is the quoted introduction to Victoria’s research by Carol, followed by the link to Victoria’s results: “In any such study of even a few hun...

deCode discovers cousin marriages bear more offspring

Genetics and Health — Sun, 10 Feb 2008 20:30:19 +0100

This study provides the most comprehensive answer yet to the longstanding question of how kinship affects fertility in humans. For example, for women born between 1800 and 1824, those with a mate related at the level of a third cousin had an average of 4.04 children and 9.17 grandchildren, while those related to their mates as eighth cousins or more distantly had 3.34 children and 7.31 grandchildren. For women born in the period 1925-1949 with mates related at the degree of third cousins, the average number of children and grandchildren were 3.27 and 6.64, compared to 2.45 and 4.86 for those with mates who were eighth cousins or more distantly related. The findings hold for every 25-year interval studied, beginning with those born in the year 1800 up to the present day. Because of the stre...

Scientists create ‘three parent’ embryo

Genetics and Health — Tue, 05 Feb 2008 17:29:56 +0100

Scientists from Newcastle University, UK led by Professor Patrick Chinnery, have created an embryo with three separate parents. The team believe the technique could help to eradicate a whole class of hereditary diseases, including some forms of epilepsy and ensure women with genetic defects do not pass the diseases on to their children. Ten severely deformed embryos, left over from traditional fertility treatment were created using DNA from a man and two women in lab tests. Within hours of their creation, the nucleus, containing DNA from the mother and father, was removed from the embryo, and implanted into a donor egg whose DNA had been largely removed. The only genetic information remaining from the donor egg was the tiny bit that controls production of mitochondria - around 16,0...

Exercise, telomeres and looking years younger!

Genetics and Health — Sat, 02 Feb 2008 10:28:09 +0100

Human chromosomes (grey) capped by telomeres (white) We all know the benefits of regular exercise but scientists now have proof that it can really make you look younger! Telomeres, regions of highly repetitive DNA at the end of a linear chromosome shorten over time. The shortening of telomeres is strongly correlated with ageing and it is believed that telomeres have a function in the ageing process. Latest research indictates that the rate of shortening of telomeres increases with an increasingly sedentary lifestyle. A group of 2,401 white twins was studied by Lynn F. Cherkas, Ph.D., of King’s College London, and colleagues. The team administered questionnaires related to physical activity level, smoking habits, and social and economic factors. Notably, the participants also pro...

deCode uncovers genetic variants driving male-female evolutionary changes

Genetics and Health — Fri, 01 Feb 2008 15:27:51 +0100

Scientists from deCODE genetics have reported the discovery of two common, single-letter variants in the sequence of the human genome (SNPs) that regulate one of the principle motors of evolution. Versions of the two SNPs, located on chromosome 4p16, have a genome-wide impact on the rate of recombination - the reshuffling of the genome that occurs in the formation of eggs and sperm. Recombination is largely responsible for generating human diversity, the novel configurations of the genome that enable each species to adapt and evolve in an ever-changing environment. Yet remarkably, the versions of the SNPs that increase recombination in men decrease it in women, and vice versa. The deCODE team identified the SNPs through a genome-wide analysis of more than 300,000 SNPs in approximately ...

Susceptibility to cold sores probably inherited

Genetics and Health — Wed, 30 Jan 2008 10:04:12 +0100

Herpes simplex virusThere’s a high probability that people who are prone to herpes simplex virus (HSV) outbreaks can inherit that susceptibility through their genes, University of Utah researchers report in The Journal of Infectious Diseases. Researchers have identified a region on the long arm of human chromosome 21 with high odds - at least 1,000-to-1 - of being linked to cold sore susceptibility. The researchers further say they pinpointed six specific genes in that chromosomal region as candidates for making people prone to outbreaks of cold sores (also called “fever blisters”). Cold sores occur when the herpes virus reactivates from its quiescent state within the nerve, infecting the lip, nose, or face. Discovery of the probable link could lead to the development of ...

‘Telepathic’ genes

Genetics and Health — Mon, 28 Jan 2008 11:48:14 +0100

New research has shown evidence that genes have the ability to recognize similarities in each other from a distance, without any proteins or other biological molecules aiding the process. This discovery could explain how similar genes find each other and group together in order to perform key processes involved in the evolution of species. According to new research from Imperial College, UK published this week in the Journal of Physical Chemistry B, this ability to seek each other out could be the key to how genes identify one another and align with each other in order to begin the process of ‘homologous recombination’ - whereby two double-helix DNA molecules come together, break open, swap a section of genetic information, and then close themselves up again. Recombination i...

GEN2PHEN web based project to capture health & disease genetic knowledge

Genetics and Health — Tue, 22 Jan 2008 09:57:30 +0100

The EU funded GEN2PHEN project plans to internationally orchestrate the electronic gathering and use of data that show how gene sequences (’genotypes’) contribute to individual differences in disease, drug response, and other characteristics (’phenotypes’). These relationships (usually in the form of “genotype-phenotype” information stored in scattered databases) are deemed to become essential for future prognosis, diagnosis and treatment of diseases. GEN2PHEN will build a set of database components, tools and technologies that will help all research results pertaining to genome variation and disease to be properly integrated and immediately available for holistic analysis via the internet. The project will deploy a major internet portal, called the R...

Human-animal embryo hybrid testing given go ahead in UK

Genetics and Health — Mon, 21 Jan 2008 13:31:31 +0100

Early embryos yield stem cells,(photo courtesy of BBC news www.bbc.co.uk/news) The Uk’s fertility regulator Human Fertilisation and Embryology Authority (HFEA) has given the green light to two teams of scientists for the creation of hybrid human-animal embryos. Scientists, research institutions and patient groups have challenged the UK government for much of the last year: the Department of Health wanted to prevent the creation of human-animal hybrid embryos - which would be used to create stem cells for medical research - but scientists argued it would slow down crucial work into treatments for diseases including Alzheimer’s, Parkinson’s and diabetes. Reason eventually triumphed and the government has now backed down. Scientists from King’s College London and ...

Sex in fungi: MAT locus cloned from a Zygomycete

Fungal Genomes and Comparative Genomics — Sun, 13 Jan 2008 23:39:22 +0100

On the cover of this week's Nature is a picture of Phycomyces blakesleeanus highlighting the discovery of the MAT locus in this Zygomycete fungus from Alex Idnurm and Joe Heitman and colleagues. While it was previously known that Zygomycetes (the Orange lineage represented by R. oryzae in the tree below) mate, the specific locus has until now, never been discovered. The authors in this study identified the MAT locus through a sequence search looking for HMG-box genes knowing that these are found the Mating Type locus in Basidiomycetes and Ascomycetes. They confirmed the identity through a through set of experiments that included PCR, sequencing and crosses of (+) and (-) strains of P. blakesleeanus, and Southern blots. (more...) © Jason Stajich for Fungal Genomes and Comparative...

b5’s Kids Health Notes and Autism Vox - CNTNAP2 implicated in autism

Genetics and Health — Sat, 12 Jan 2008 08:28:43 +0100

Grace at Kids Health Notes and Kristina at Autism Vox have both written about the gene CNTNAP2 being unequivocally implicated in Type 1 Autism. In her article CNTNAP2, an autism susceptibility gene which I highly recommend, Kristina writes a personal account of her ongoing experience with her son Charlie’s autism and discusses the recent research findings. Do read Grace’s article titled CNTNAP2 ‘unequivocally implicated’ in Type 1 autism which summarizes the three main pieces of research appearing in the American Journal of Genetics. For the scientists: Contactin Associated Protein-Like 2 is also known as CDFE; NRXN4; CASPR2; DKFZp781D1846. This gene encodes a member of the neurexin family which functions in the vertebrate nervous system as cell adhesion molecule...

More on CNTNAP2, an Autism Susceptibility Gene, and Parent of Origin Bias

Autism Vox — Sat, 12 Jan 2008 06:46:58 +0100

CNTNAP2 (contactin-associated proteinlike 2) is a gene that indicates susceptibility for autism, as noted in a new study by Alarcón et al., in the January 10th American Journal of Human Genetics. Another article in the same journal by Aravinda Chakravarti et al. of the Johns Hopkins University School of Medicine has found that a variation in CNTNAP2 raises the risk of having autism, especially when the gene with that variation is inherited from the mother. CNTNAP2 is a member of the neurexin superfamily and is, as noted in the January 11th Science Daily, “makes a protein that enables brain cells to communicate with each other through chemical signals and appears to play a role in brain cell development.” The researches studied two groups of first participants. The first was ...

Cntnap2

Autism Vox — Thu, 10 Jan 2008 18:03:37 +0100

More news studies on the genetics of autism: CNTNAP2 is contactin-associated proteinlike 2; it is “a blueprint of sorts for an important protein involved in the ability of brain cells to communicate with each other properly,” today’s ABC news reports. Three separate studies, published today in American Journal of Human Genetics, confirm a link between autism and this gene, which is associated with language and thought in young children. Dietrich Stephan comments on the three studies in Unraveling Autism. Share This (Source: Autism Vox)

Great genetics based article on Autism at b5’s Autism Vox

Genetics and Health — Thu, 10 Jan 2008 08:23:37 +0100

My colleague Kristina at Autism Vox has written a great article about the genetic basis of Autism. Research has indicated that either a deletion or a duplication of a section of chromosome 16 seems to contribute strongly to susceptibility to autism. I highly recommend you click on the following link to read more: http://www.autismvox.com/like-father-like-son/ Elaine Warburton Share This (Source: Genetics and Health)

Breast cancer risk varies amongst BRCA gene carriers

Genetics and Health — Thu, 10 Jan 2008 07:26:35 +0100

Breast awareness and regular checking are important in early detection of breast cancer Further to my articles on the BRCA breast cancer genes, an American and Danish study has found the risk of developing cancer amongst carriers of the BRCA1 and 2 breast cancer gene mutations varies greatly. The risk of breast cancer in BRCA1 and BRCA2 mutation carriers has been examined in many studies, but relatively little attention has been paid to the degree to which the risk may vary among carriers. This knowledge of risk is important when deciding cancer treatment and prevention. The study lead Dr Colin Begg of the Memorial Sloan-Kettering Hospital in New York genotyped 2,098 women for mutations in BRCA1 and 2 genes. The women were participants in the Women’s Environmental Cancer an...

Like Father, Like Son: Chromosome 16 and susceptibility to autism

Autism Vox — Thu, 10 Jan 2008 06:42:51 +0100

Conclusions We have identified a novel, recurrent microdeletion and a reciprocal microduplication that carry substantial susceptibility to autism and appear to account for approximately 1% of cases. We did not identify other regions with similar aggregations of large de novo mutations. The January 10th New York Times comments: The finding is not likely to improve diagnosis or treatment for most children struggling with autism or related problems anytime soon, experts said, but it points to a specific chunk of DNA where some developmental problems could originate. ………….. The rate of the chromosome alteration in a group of normally developing people was one in 10,000. “The analysis tells us that this is a very strong risk factor for autism, increasing the risk ...

Down’s Syndrome gene may protect against cancer

Genetics and Health — Sun, 06 Jan 2008 16:13:30 +0100

Male Down’s Syndrome with trisome at chromosome 21 People with Down’s Syndrome are less likey to get solid tumor cancers, research from Johns Hopkins University has revealed. Up to 95% of Down’s syndrome cases are caused by “trisomy 21″, in which the baby has three, rather than two, copies of chromosome 21, and the hundreds of genes it contains. Advances in medical management of Down’s Syndrome patients has increased life expectancy from around 30 years of age to over 60 years of age. This increase led to some studies finding that adults with Down’s syndrome appear to have less chance of developing certain cancers which involved “solid” tumors. On mouse studies, the Johns Hopkins team pinpointed a single gene, Ets2, and found t...

New fertility technique allows boys born with extra X chromosome (Klinefelter’s) to become fathers

Genetics and Health — Wed, 02 Jan 2008 08:44:40 +0100

Klinefelter’s Syndrome Almost one in every 500-1,000 males babies are born with an extra X chromosome. This condition is known as Klinefelter’s Syndrome. These men are also known as XXY males or 47XXY males. Klinefelter’s syndrome is a condition that occurs in men who have an extra X chromosome in most of their cells. The syndrome can affect different stages of physical, language and social development. The most common symptom is infertility. Because they often don’t make as much of the male hormone testosterone as other boys, teenagers with Klinefelter’s syndrome may have less facial and body hair and may be less muscular than other boys (see the diagram above). They may have trouble using language to express themselves. They may be shy and hav...

More Good News From Gleevec

Cancer Commentary — Wed, 12 Dec 2007 09:31:10 +0100

The targeted cancer pill – Gleevec - has been approved for the treatment of gastrointestinal stromal tumors, pediatric CML, as well as five additional rare cancers. While it has been reported to have saved more than 100,000 lives, Gleevec is now saving more children with a dire leukemia (Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) ), as well as preventing disease progression with long term use in adults with chronic myeloid leukemia (CML). Such were the data reported by Oregon Health & Science University (OSHU) at the recent annual meeting of the American Society of Hematology: “Data at this weekend’s meeting continues to show how much Gleevec has completely changed the outlook for so many, many patients facing cancer. Researchers delivered news that G...

Which came first? The cancer or its chromosomes?

Gene Sherpas: Personalized Medicine and You — Wed, 04 Jul 2007 01:20:00 +0100

Every now and again I like to throw out the old paradigms and put in some new. Geneticists love this......The So Called "Paradigm Shift"Back in 2005 this was done with Marfan's disease. It is an example I use to teach my students that what they may have learned is wrong. It is wrong because medical teaching is only built on science that has a very limited set of knowns and an immense set of unknowns.This paradigm shift is already in the making. The classical model of how a cancer develops is called the "two-hit" hypothesis. It states that in order to have uncontrolled growth of cells i.e. cancer, you need two hits to genes. Mostly you have to have at least 2 mutations. Sometimes you activate a gene by mutation and other times you may silence the genes. For the last 30 years the view of can...