In PLOS Genetics, Yale School of Medicine researchers describe signs of positive selection spanning common variants implicated in autism spectrum disorder (ASD). The team modeled natural selection scenarios using allelic patterns from genome-wide association studies of ASD, attention deficit hyperactivity disorder, bipolar disorder, major depressive disorder, and schizophrenia, identifying variants with incomplete selection in ASD. Following additional analyses, including a look at brain gene expression, the authors "hypothesize that certain ASD risk alleles were under positive selection during human evolution due to their involvement in neurogenesis and cognitive ability."
The gut microbiome appears to differ between more or less active women, according to a PLOS One study. Spanish researchers used a combination of 16S ribosomal RNA sequencing and quantitative PCR to assess gut microbial community members in 40 women between the ages of 18 years and 40 years old with known dietary habits and accelerometer-measured activity levels taken over a week. Their analysis uncovered differences in the levels of at least 11 microbial genera in the gut between the 19 active and 21 sedentary women.
Finally, a team from Australia reports on results from an analysis of cross-species transmission analysis of viruses from 19 families in PLOS Pathogens. The researchers did a quantitative co-phylogenetic analysis of 12 RNA viruses and seven DNA viruses known for infecting a range of animals, plants, and/or insects, in an effort to distinguish between cases of co-divergence and cross-species transmission. "Overall, we show that cross-species transmission plays a major role in virus evolution," the authors write, "with all the virus families studied here having the potential to jump host species, and that increased sampling will likely reveal more instances of host jumping."