In PLOS One, researchers report on a genetic analysis of a 33,000-year-old dog skull found in a cave in Siberia's Altai Mountains. A team from the US, Russia, Finland, and Spain performed targeted mitochondrial DNA sequencing on jaw bone and tooth samples from the skull, showing that these samples matched one another and clustered genetically with domestic dogs. The aged canine remnants shared fewer genetic similarities with modern-day wolves or with ancient wolves from the Pleistocene period whose remains were recovered from the same cave. "These results suggest a more ancient history of the dog outside of the Middle East or East Asia," authors of the study say, "previously suggested as centers of dog origin."
For more on the study, check out a related story in our sister publication GenomeWeb Daily News.
Complex traits are often a consequence of common variants falling across many genes, according to a PLOS Genetics study. Researchers from Australia and Korea assessed genotyping data for almost 7,200 individuals from Korea, using a combination of genome-wide estimation and partitioning analyses to look at how well sets of common SNPs explained 49 complex traits — from obesity and blood pressure to liver, lung, and kidney functions. For almost all of the traits tested, SNPs spread across the genome seemed to explain a considerable proportion of the trait's heritability, pointing to widespread polygenicity among complex human traits, study authors argued. "Despite examples where a few variants explain a substantial amount of variation," they say, "all these results are consistent with polygenicity being ubiquitous for most complex traits."
A team from Nigeria and Israel cataloged vector-borne pathogens found in Nigerian dogs and three tick species that pester them for a study in PLOS Neglected Tropical Diseases. The researchers used targeted PCR sequencing to track down vector-borne pathogens in blood and tick samples taken from 181 dogs in Nigeria. The analysis uncovered a wide range of pathogens known for infecting either animals or humans, they note, with around 63 percent of the ticks and more than three-quarters of the dogs apparently carrying at least one vector-borne pathogen.