In DepthGenetics

Human mutation rate a legacy from our past

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Science  13 Apr 2018:
Vol. 360, Issue 6385, pp. 143
DOI: 10.1126/science.360.6385.143

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Summary

Humans should be more like paramecia. That's because their mutation rate is orders of magnitude lower than a human's. Those rates increase when genes involved in copying or repairing DNA stop working correctly. Although some mutations are good for generating variety that allows organisms to adapt to changing environments, too many can cause disease and birth defects. At a meeting in Tempe, Arizona, researchers documented mutation rates in dozens of species and found that the species's specific rate is inversely related to the so-called "effective population" size. Small populations are less able to get rid of or compensate for genetic changes that increase mutation rate. In the past, mutation rates were thought to be so stable that they were "molecular clocks" useful for dating species' divergences. But researchers are now recognizing that mutation rates vary from species to species.