Editor's Note: Some of the articles described below are not yet available at the PNAS site, but they are scheduled to be posted some time this week.
For a paper scheduled to appear in PNAS this week, investigators from Austria, Bosnia-Herzegovina, and Germany describe common variants with apparent ties to binding by complement factor H (CFH), a regulator for an alternative complement pathway implicated in age-related macular degeneration and other autoimmune conditions. Through a genome-wide association study that included more than 1,800 individuals, the team searched for common variants corresponding with binding patterns for CFH and CFH splice variants in blood plasma samples, measured with an enzyme-linked immunosorbent assay. The search highlighted variants within genes from the CFH family in healthy individuals, the authors report, noting that SNPs corresponding to deletions in genes such as CFHR3 or CFHR1 "might be used as a novel stratification tool for risk assessment in a healthy population for the development of diseases associated with increased oxidative stress and aging."
A University of New Brunswick-led team presents findings from a DNA metabarcoding-based study of ecosystem changes — particularly within aquatic macroinvertebrate communities — in an inland boreal wetland in northern Alberta known as the Peace-Athabasca Delta. Using DNA metabarcoding and sequencing, multispecies occupancy modeling, and microscopy-based identification centered on morphology, the researchers assessed hundreds of samples collected in the Peace-Athabasca Delta over several years, within the context of space, time, temperature, and wetland flooding frequency. They report that "DNA metabarcoding detected a much broader range of taxa and more taxa per sample compared to traditional morphological identification, and was essential to identifying significant responses to flood and thermal regimes."
Researchers from Australia, Germany, the US, and Singapore report on exogenous retroviruses found in Australian bats. Starting with a metagenomic RNA- and RT-PCR-based survey of bat feces, blood, urine, and oral swab samples collected from bats in a rainforest in Australia, along with sequence database searches, the team saw several koala retrovirus (KoRV)-related gammaretroviruses in bats from Australia and Asia. One of those viruses, dubbed the Hervey pteropid gammaretrovirus (HPG), first turned up in scat samples from the Australian black flying fox bat, the authors note, and was subsequently found in samples from other bat species from Australia's northeast. Their results suggest HPG, "the first reproduction-competent retrovirus found in bats," falls in a viral group that is basal to other KoRV-related viruses and appears to have the ability to infect both bat and human cells in in vitro experiments.