Friday, April 24, 2015

Wooly Mammoth Genome

Complete genomes reveal signatures of demographic and genetic declines in the woolly mammoth. 2015. Palkopoulou et al. Current Biology.

Before the world's last woolly mammoth took its final breath, the iconic animals had already suffered from a considerable loss of genetic diversity. These findings, based on a comparison of the first complete genome sequences isolated from two ancient mammoth specimens.

One of those mammoths, representing the last population on Russia's Wrangel Island, is estimated to have lived about 4,300 years ago. The other specimen, from northeastern Siberia, is about 44,800 years old. The younger of the two specimens showed much lower genetic variation, including large stretches of DNA with no variation whatsoever - the mark of living in a very small population in which related individuals unavoidably mate with each other. PR