In this week's Science, two independent research groups publish studies examining ancient genomes, providing new insights into human evolution. In the first study, a team led by scientists from the Max Planck Institute sequenced the genome of a female Neanderthal from about 50,000 years ago found in a cave in Croatia. Their data suggest that Neanderthals lived in small groups, but did not indicate the levels of inbreeding observed in analyses of other Neanderthals. The newly sequenced female was also found to be more closely related to the Neanderthals that mixed with the ancestors of present-day humans living outside of sub-Saharan Africa than a previously sequenced Neanderthal from Siberia. In the second study, a University of Copenhagen-led group analyzed the genomes of four archaic, anatomically modern humans that were found at a burial site in Russia. The individuals lived between 34,600 years and 33,600 years ago, were all male, and unrelated to each other. These individuals displayed significant genetic diversity despite being a part of a small genetic population, suggesting that they mated outside of their own group. GenomeWeb has more on these and another study here.
Also in Science are three reviews discussing the growing field of single-cell genomics. The first review provides a look at how single-cell transcriptomics has advanced the study of the immune system and examines the use of single-cell techniques in investigating the adaptive and innate components of immunity. The second focuses on single-cell sequencing in neuroscience, highlighting new techniques that can help link molecular cell types to morphological, physiological, and behavioral correlates, and touching on the challenges that still remain. The final review looks at single-cell epigenomics, and notes that although the development of new techniques in the field has lagged behind RNA sequencing, progress is being made answering questions like how epigenetic changes relate to chromatin structure. It also discusses new techniques for tracking cell lineages, and for understanding cell fate decisions, identity, and function.