In this week's Nature, an international team of researchers presents a study that examines the role of rare and lower-frequency gene variants in type 2 diabetes, finding that these genetic variations do not substantially contribute to disease risk. The investigators sequenced whole genomes from about 2,700 people, as well as the exomes of about 13,000 individuals from five ancestry groups, both with and without type 2 diabetes. They also analyzed an additional 112,000 with targeted genotyping. They found that nearly all of the variants associated with type 2 diabetes are common and show up in regions of the genome previously identified through genome-wide association studies. GenomeWeb has more on this study, here.
Also in Nature, a group led by investigators from the Allen Institute for Brain Science publish a new gene expression atlas in the pre- and postnatal primate brain, providing a resource that may be used to study neurodevelopmental disorders. The high-resolution map of rhesus monkey brain development shows how gene expression changes over time from early gestation to young adulthood, and reveals that the most dramatic changes occur before birth. Notably, genes linked to neurodevelopmental disorders were shown to be co-expressed in disease-specific patterns within the developing neocortex. The work also suggests that human developmental gene expression patterns are more similar to monkeys than rodents, confirming the utility of the rhesus monkey as a model of human brain development and disease.
Lastly, in Nature Communications, a Wellcome Trust Sanger Institute-led team reported data linking mutations in the gene MC1R, which is associated with red hair and freckles, with increased mutations in skin cancer. The gene is involved in skin pigmentation, and carrying two copies of a particular variant is known to be associated with red hair. In the study, the team analyzed two previously published datasets composed of melanoma samples, including sequenced DNA information from the samples. They found that patients with one or two copes of the MC1R variant had an increased number of mutations in the DNA of their melanoma samples. The researchers also found that age was associated the number of mutations in the samples, with a 1.7 percent increase for each year. GenomeWeb also covers this study, here.