Skip to main content
Premium Trial:

Request an Annual Quote

This Week in Science: Feb 23, 2018

In Science this week, an international research team presents a genomic study suggesting that the oldest known domesticated horse population — which came from the Eneolithic Botai culture of the Central Asian steppes roughly 5,500 years ago — did not give rise to modern-day domesticated horses. By analyzing the genomes of 88 ancient and modern horses — including 20 from the Botai region — they found that all domestic horses from around 4,000 years ago to present only show just 2.7 percent of Botai-related ancestry. "This indicates that a massive genomic turnover underpins the expansion of the horse stock that gave rise to modern domesticates, which coincides with large-scale human population expansions during the Early Bronze Age," they write. GenomeWeb has more on this study, here.

Also in Science, a Delft University of Technology-led team describes how it visualized, for the first time, structural maintenance of chromosome (SMC) protein complexes spatially organizing chromosomes by extruding DNA into large loops. By tethering both ends of a double-stranded piece of DNA to a surface and staining it, they could track it as the complexes worked along the strand. They found that a single condensin complex is able to extrude tens of kilobase pairs of DNA at a force-dependent speed of up to 1,500 base pairs per second, using the energy of ATP hydrolysis. Notably, the DNA loop extrusion process is asymmetric, which demonstrates that condensin anchors onto DNA and reels it in from only one side, the authors write. "Active DNA loop extrusion by SMC complexes may provide the universal unifying principle for genome organization," they add.

The Scan

Genetic Ancestry of South America's Indigenous Mapuche Traced

Researchers in Current Biology analyzed genome-wide data from more than five dozen Mapuche individuals to better understand their genetic history.

Study Finds Variants Linked to Diverticular Disease, Presents Polygenic Score

A new study in Cell Genomics reports on more than 150 genetic variants associated with risk of diverticular disease.

Mild, Severe Psoriasis Marked by Different Molecular Features, Spatial Transcriptomic Analysis Finds

A spatial transcriptomics paper in Science Immunology finds differences in cell and signaling pathway activity between mild and severe psoriasis.

ChatGPT Does As Well As Humans Answering Genetics Questions, Study Finds

Researchers in the European Journal of Human Genetics had ChatGPT answer genetics-related questions, finding it was about 68 percent accurate, but sometimes gave different answers to the same question.