Discover the Science of Health
Researchers have identified a genomic variant strongly associated with sensitivity to the sun, brown hair, blue eyes — and freckles. In the study of Icelanders the researchers uncovered an intricate pathway involving the interspersed DNA sequence, or non-coding region, of a gene that is among a few dozen that are associated with human pigmentation traits. The study by an international team including researchers from the National Institutes of Health was reported in the journal Cell [1].
According to an international study led by researchers from the Virginia Commonwealth University (VCU) School of Pharmacy, multiple genes contribute to risk for schizophrenia and appear to function in pathways related to transmission of signals in the brain and immunity [1]. The discovery provides scientists with a better understanding the molecular and biological mechanisms involved with schizophrenia that may improve disease management and identify new drug targets. The study is published in the April issue of JAMA Psychiatry.
Inhaled corticosteroids are used by millions of asthma patients every day. However, as with all treatments to control asthma, there is marked patient-to-patient variability in the response to treatment. New research published today in the New England Journal of Medicine (NEJM) has identified a genetic variant associated with the response to inhaled corticosteroids [1]. Investigators have found that asthma patients who have two copies of a specific gene variant responded only one-third as well to steroid inhalers as those with two copies of the regular gene.
Small genetic differences between individuals help explain why some people have a higher risk than others for developing illnesses such as diabetes or cancer. Recently in the journal Nature, the 1000 Genomes Project, an international public-private consortium, published the most comprehensive map of these genetic differences, called variations, estimated to contain approximately 95 percent of the genetic variation of any person on Earth.
High blood pressure or hypertension affects more than one in three people worldwide and is a major cause of strokes, heart attacks and heart failure [1]. The degree with which blood pressure traits can be inherited suggests a genetic component. However, limited consistent evidence of genes associated with blood pressure have been produced. A new study in the journal Nature Genetics reports for the first time a number of genes showing significant associations with blood pressure and hypertension across the genome [2].
Although large-scale genome-wide association studies (GWAS) have been used successfully to identify genes associated with common diseases and traits, studies on blood pressure or hypertension have failed to identify loci at a genome-wide significant threshold (p-value < 5 x 10-8). The significance of GWAS data relies on several variables, including the accuracy of phenotypic measures, density of markers and size of the study population. Thus, if blood pressure variation in the general population is due to multiple genetic factors with small effects, a very large sample size is needed to identify them.
