:: Posted by American Biotechnologist on 03-28-2012
A hidden and never before recognized layer of information in the genetic code has been uncovered by a team of scientists at the University of California, San Francisco (UCSF) thanks to a technique developed at UCSF called ribosome profiling, which enables the measurement of gene activity inside living cells — including the speed with which proteins are made.
By measuring the rate of protein production in bacteria, the team discovered that slight genetic alterations could have a dramatic effect. This was true even for seemingly insignificant genetic changes known as “silent mutations,” which swap out a single DNA letter without changing the ultimate gene product. To their surprise, the scientists found these changes can slow the protein production process to one-tenth of its normal speed or less.
:: Posted by American Biotechnologist on 03-12-2012
In a brief paper in the journal Bioinformatics, Brown University researchers describe a new, freely available Web-based program called Spliceman for predicting whether genetic mutations are likely to disrupt the splicing of messenger RNA, potentially leading to disease.
“Spliceman takes a set of DNA sequences with point mutations and computes how likely these single nucleotide variants alter splicing phenotypes,” write co-authors Kian Huat Lim, a graduate student, and William Fairbrother, assistant professor of biology, in an “application note” published in advance online Feb. 10. It will appear in print in April.
Spliceman can be found at fairbrother.biomed.brown.edu/spliceman.
:: Posted by American Biotechnologist on 02-02-2012
Traditional RNA isolations kits and techniques usually isolate linear RNA transcripts while discarding circular material that are thought to be unimportant. However, a new study at the Stanford School of Medicine suggests that circular RNA may play a more important role in gene expression than previously thought.
In the classical model of gene expression, the genetic script encoded in our genomes is expressed in each cell in the form of RNA molecules, each consisting of a linear string of chemical “bases”. It may be time to revise this traditional understanding of human gene expression, as new research suggests that circular RNA molecules, rather than the classical linear molecules, are a widespread feature of the gene expression program in every human cell. The results are published in the Feb. 1 issue of the online journal PLoS ONE.
:: Posted by American Biotechnologist on 11-29-2011
Scientists at Weill Cornell Medical College used genetic methods to successfully repair cleft lips in mice embryos specially engineered for the study of cleft lip and cleft palate. The research breakthrough may show the way to prevent or treat the conditions in humans.
Cleft lip and cleft palate are among the most common birth defects, with treatment requiring multiple cycles of surgery, speech therapy and orthodontics. To date, there have been very few pre-clinical methods that allow researchers to study the molecular causes of these malformations. In particular, there has been a lack of animal models that accurately reflect the contribution of multiple genes to these congenital deformities in humans.
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:: Posted by American Biotechnologist on 11-23-2011
New research sifts through the entire genome of thousands of human subjects to look for genetic variation associated with height. The results of the study, published by Cell Press in the December issue of the American Journal of Human Genetics, suggest that uncommon genetic deletions are associated with short stature.
Height is a highly heritable trait that is associated with variation in many different genes. “Despite tremendous recent progress in finding common genetic variants associated with height, thus far these variants only explain about 10% of the variation in adult height,” explains senior study author, Dr. Joel N Hirschhorn, from Children’s Hospital Boston and the Broad Institute. “It has been estimated that about half of height variation could eventually be accounted for by the sorts of variants we’ve been looking at, so it is possible that other types of genetic variants, such as copy number variants (CNVs), may also contribute to the genetic variation in stature.”
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