In this week's Nature, a Harvard University-led team reports the identification of genomic regions affecting parental care in two mouse species, as well as a role for the hormone vasopressin in one specific care behavior. The researchers focused on two closely related species of mice — the promiscuous deer mouse and the monogamous old-field mouse — and show that they each have significant heritable differences in parental behavior. Using quantitative genetics, they uncovered 12 genomic regions that affect parental care, eight of which have sex-specific effects, suggesting that parental care can evolve independently in males and females. They also found that some regions affect parental care broadly, whereas others affect specific behaviors including nest building. Vasopressin was differentially expressed in the hypothalamus of the two mouse species, with increased levels associated with less nest building. And, by manipulating vasopressin-releasing neurons in the hypothalamus, the researchers were able to modify levels of nest building performed by the mice. The work sheds new light on the neurobiology underlying complex social behaviors.
And in Nature Genetics, a multi-institute research team publishes a large-scale analysis of genetic variants that uncovers new loci associated with atrial fibrillation. The investigators performed several large-scale, trans-ancestry meta-analyses of common and rare variant association studies: genome-wide association studies that included 17,931 individuals with atrial fibrillation and 115,142 referents, and exome-wide association studies and rare variant association studies involving 22,346 cases and 132,086 referents. They found 12 new loci that exceeded genome-wide significance, implicating genes involved in cardiac electrical and structural remodeling — nearly doubling the number of known genetic loci for atrial fibrillation.
Also in Nature Genetics, researchers from the Riken Center for Integrative Medical Sciences and elsewhere report new genetic loci associated with atrial fibrillation, including ones specific to the Japanese population. They performed a Japanese-specific genome-wide association study that included 8,180 atrial fibrillation cases and 28,612 controls, with follow-up in an additional 3,120 cases and 125,064 controls. In addition to replication previously identified loci, they found six new loci, five of which were specifically associated with atrial fibrillation in the Japanese population when compared with data from individuals of European ancestry. This finding suggests there might be different genetic factors affecting susceptibility across ancestry groups, the authors write.
GenomeWeb has more on the atrial fibrillation studies, here.