http://medicalxpress.com/ en-us Medical Xpress internet news portal provides the latest news on Health and Medicine. (Medical Xpress)—Researchers at the Wellcome Trust Sanger Institute and University of Cambridge have unpicked genetic variants that affect the formation of blood cells. They found that around a third of the variants play a role in gene regulation, and that the action of these variants is specific to individual cell types. The discovery is an important step towards unravelling the biological mechanisms behind variants identified in genome-wide scans of blood traits. http://medicalxpress.com/news/2013-04-closer-biology-genetic-variants-linked.html Genetics Wed, 17 Apr 2013 09:43:41 EST news285410601 Scientists at Karolinska Institutet in Sweden and the University of Helsinki in Finland have shown that the "switches" that regulate the expression of genes play a major role in the development of cancer. In a study, published in Science, they have investigated a gene region that contains a particular single nucleotide variant associated with increased risk for developing colorectal and prostate cancers – and found that removing this region caused dramatic resistance to tumor formation. http://medicalxpress.com/news/2012-11-scientists-gene-important-cancer.html Cancer Thu, 01 Nov 2012 14:00:37 EST news270997228 Since the sequencing of the human genome in 2001, all our genes – around 20,000 in total – have been identified. But much is still unknown – for instance where and when each is active. Next to each gene sits a short DNA segment, and the activity of this regulatory segment determines whether the gene will be turned on, where and how strongly. These short regulatory segments are as – if not more – important than the genes, themselves. Indeed, 90% of the mutations that cause disease occur in these regulatory areas. They are responsible for the proper development of tissues and organs, determining, for instance, that eye cells – and only eye cells – contain light receptors, while only pancreatic cells function to produce insulin. Clearly, a deeper understanding of this regulatory system – its mechanisms and possibilities for malfunction – may lead to advances in biomedical research, especially in developing targeted therapies for individual patients. http://medicalxpress.com/news/2012-09-uncovering-genome-regulatory-code.html Genetics Mon, 10 Sep 2012 09:20:51 EST news266487643 Changes to just three genetic letters among billions led to evolution and development of the mammalian motor sensory network, and laid the groundwork for the defining characteristics of the human brain, Yale University researchers report. http://medicalxpress.com/news/2012-05-genetic-huge-human-brain.html Genetics Wed, 30 May 2012 13:00:01 EST news257590511 Researchers at the Hebrew University of Jerusalem have achieved, for the first time, the generation of neuronal cells from stem cells of Fragile X patients. The discovery paves the way for research that will examine restoration of normal gene expression in Fragile X patients. http://medicalxpress.com/news/2012-05-stem-cell-paves-fragile-retardation.html Medical research Tue, 22 May 2012 10:53:17 EST news256902788 Chromosomes, the molecular basis of genetic heredity, remain enigmatic 130 years after their discovery in 1882 by Walther Flemming. New research published online in Nature by the team of Edith Heard, PhD, from the Curie Institute and Job Dekker, PhD, from the University of Massachusetts Medical School (UMMS), reveals a new layer in the complex organization of chromosomes. The scientists have shown that chromosomes fold in a series of contiguous "yarns" that harbor groups of genes and regulatory elements, bringing them in contact with each other and allowing them to work in a coordinated manner during development. http://medicalxpress.com/news/2012-04-discovery-reveals-chromosomes-yarns.html Genetics Wed, 11 Apr 2012 14:41:21 EST news253373802 The olfactory sensory neurons in the nasal mucosa perceive the myriad smells in the air with the aid of odorant receptors. Each sensory neuron chooses one and only one receptor gene for expression. The probability that a particular receptor gene is chosen for expression determines how many olfactory sensory neurons in total produce this receptor type. Scientists from the Max Planck Institute of Biophysics in Frankfurt have unveiled an aspect of how the probability of the choice of an odorant receptor gene is regulated in olfactory sensory neurons. Regulatory elements in the genome regulate the probability of the choice of individual odorant receptor genes within a gene cluster. These elements act as on-off-switches for gene choice, but they do not regulate the number of receptor molecules that are produced by a cell once a particular gene is chosen for expression. http://medicalxpress.com/news/2011-11-gene-odorant-receptors.html Genetics Fri, 11 Nov 2011 12:52:29 EST news240238340 An army of immune cells circulates the human body to protect against its potential foes—viruses, bacteria, cancer cells, and other invaders. Because the immune system cannot know what to expect, it must be prepared to fend off virtually any foreign pathogen it might encounter. Now, Howard Hughes Medical Institute scientists have identified a genetic regulator that controls the reshuffling of gene segments that immune cells use to manufacture billions of distinct antibodies and pathogen-recognizing receptors from a limited number of genes. http://medicalxpress.com/news/2011-09-genetic-immune-diverse-threats.html Genetics Sun, 11 Sep 2011 13:59:30 EST news234968361 Researchers have developed a new strategy to improve the outcome of genome-wide association (GWA) studies. http://medicalxpress.com/news/2011-06-approach-link-genome-wide-association-biological.html Genetics Thu, 30 Jun 2011 17:40:36 EST news228674413