“Novel Loci Associated With Usual Sleep Duration: the CHARGE Consortium Genome-Wide Association Study”, 2015 (; backlinks; similar):
Usual sleep duration is a heritable trait correlated with psychiatric morbidity, cardiometabolic disease and mortality, although little is known about the genetic variants influencing this trait.
A genome-wide association study (GWAS) of usual sleep duration was conducted using 18 population-based cohorts totaling 47,180 individuals of European ancestry. Genome-wide statistically-significant association was identified at two loci. The strongest is located on chromosome 2, in an intergenic region 35–80-kb upstream from the thyroid-specific transcription factor PAX8 (lowest p = 1.1 × 10−9). This finding was replicated in an African-American sample of 4771 individuals (lowest p = 9.3 × 10−4). The strongest combined association was at rs1823125 (p = 1.5 × 10−10, minor allele frequency 0.26 in the discovery sample, 0.12 in the replication sample), with each copy of the minor allele associated with a sleep duration 3.1 min longer per night. The alleles associated with longer sleep duration were associated in previous GWAS with a more favorable metabolic profile and a lower risk of attention deficit hyperactivity disorder.
Understanding the mechanisms underlying these associations may help elucidate biological mechanisms influencing sleep duration and its association with psychiatric, metabolic and cardiovascular disease.