In this week's Nature Genetics, a team led by researchers at the Brown University School of Public health report a genetic variant that increases the risk of obesity in Samoans, providing new insights into the genetics of a population with the highest prevalence of obesity in the world. The researchers conducted a genome-wide association study in roughly 3,000 Samoans and found a variant of the gene CREBRF that is associated with increased body mass index, percentage body fat, and fasting glucose levels, among other traits. Due to the founder effect, the variant is common in Samoans, but rare in other populations and is believed to increase fat storage while decreasing energy use as a safeguard against times of food scarcity. GenomeWeb has more on this here.
Also in Nature Genetics, a multi-institute team of scientists publishes the results of genome-wide association analyses that identified new risk variants for the neurodegenerative disease amyotrophic lateral sclerosis (ALS). The investigators analyzed the genomic sequences of more than 15,000 ALS patients and more than 25,000 controls, identifying a gene associated with ALS risk and two new risk loci, as well as finding evidence of ALS being a complex genetic trait with a polygenic architecture. The study points to the importance of examining large samples with full genome coverage to uncover rare causal variants that underpin ALS, the researchers say. GenomeWeb also has more on this and a related study here.
And in Nature Communications, an international research group reports data indicating that cloned sheep age normally, addressing concerns regarding the health of cloned animals. In the analysis, the investigators examined 13 aged cloned sheep aged between 7 and 9 years — including four created from the same genetic material as Dolly, the first cloned animal. While Dolly died at a young age and suffered from osteoarthritis, the researchers found that the sheep they studied are all healthy, with only one showing signs of mild osteoarthritis.