In PLOS One, researchers from South Africa, Germany, and Namibia describe findings from a phylogenetic study aimed at understanding how rabies is maintained within Namibia's kudu — the only kudu population known to carry the disease. Based on patterns in partial or whole-genome sequences from dozens of rabies virus isolates from kudu — a kind of antelope — or other animals, the team saw a distinct genetic cluster containing 42 of the 43 kudu-associated rabies viruses. These viruses were distinct from those found in jackals and other canids in the area, study authors note, which is consistent with the notion that rabies is transmitted and maintained in Namibian kudu in cycles that are independent of those detected in the canids. The investigators also uncovered kudu-specific mutations suspected of helping rabies virus survive and spread in kudu.
A fine-mapping study in PLOS Genetics suggests that at least some lipid-linked loci contain variants with population-specific effects. A large international team led by investigators at several centers in the US and Taiwan focused on dozens of loci linked to blood levels of triglyceride, high-density lipoprotein cholesterol, or low-density lipoprotein cholesterol previously. By fine-mapping these sites in tens of thousands of individuals from African-American, East Asian, or European populations, the researchers saw that most loci shared ties with the lipid-related traits of interest in at least one of the populations. But the analyses also unearthed examples of loci with distinct signals depending on the population considered. "[T]rans-ethnic high-density genotyping and analysis confirm the presence of allelic heterogeneity, allow the identification of population-specific variants, and limit the number of candidate SNPs for functional studies," they write.
Aedes albopictus mosquitoes on Réunion Island cluster genetically in ways that correspond with urban and rural mosquito populations, according to a PLOS Neglected Tropical Diseases study. French researchers embarked on an ecological and genetic study of Ae. albopictus mosquitoes, which can transmit Chikungunya, Dengue, and other disease-causing viruses. Using microsatellite DNA analyses — combined with ecological assessments that considered everything from reproduction and development to survival rates in rural and urban populations — the team got new clues to Ae. albopictus population dynamics. For instance, investigators found that though mosquito populations in rural and urban areas on Réunion Island are structured genetically, mosquitoes from natural environments can still serve as a mosquito reservoir for urban areas.