In Nature this week, a team led by Lawrence Berkeley National Laboratory researchers report the results of a multi-omics analysis of microbes in permafrost. This constantly frozen soil covers more than 20 percent of the Earth's surface and holds vast stores of carbon. The release of this carbon upon thawing is dependent on microbial responses, but little is known about the microbial communities in permafrost. Using DNA sequencing, RNA sequencing, and other omics technologies to examine the microbial communities found in Alaskan permafrost samples, the researchers created draft genomes of several novel species and identified the organisms' functional potential and activity in soils representing different states of thaw. They also uncovered novel survival strategies for potentially active microbes in permafrost.
Also in Nature, investigators led by Harvard Medical School's David Reich present data from a population genetics study of 69 Europeans who lived between 3,000 years and 8,000 years ago, revealing new details about migration patterns of early Europeans. By enriching ancient DNA libraries for a target set of almost 400,000 polymorphisms, the investigators generated genome-wide data from the individuals and found that around 7,500 years ago closely related groups of early farmers appeared in Germany, Hungary, and Spain — different from indigenous hunter-gatherers — whereas Russia was inhabited by a distinctive population of hunter-gatherers with high affinity to a 24,000-year-old Siberian. By 6,000 years to 5,000 years ago, farmers throughout much of Europe had more hunter-gatherer ancestry than their predecessors, but not in Russia. The data also point to a massive migration into the heartland of Europe from its eastern periphery around 4,500 years ago, highlighting contact between Western and Eastern Europe. GenomeWeb has more on this study here.
And in Nature Genetics, researchers from Cornell University and elsewhere publish the genome sequence of the hookworm Ancylostoma ceylanicum. They identified genes conserved among the parasites but not present in mammals, which may have promise as targets for vaccines against the parasite. Among these were 13 genes increased in expression level during an infection experiment in hamsters, producing proteins associated with survival and infection. GenomeWeb also covers this study here.