Europeans have steadily accumulated mutations for thousands of years

By Michael Marshall

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The number of mildly harmful mutations in the European population has gradually increased over the last 45,000 years, ever since modern humans arrived on the continent. The mutations may be a lingering effect of the original migration into Europe.

“These mutations that today are associated with genetic disease do not decrease over time,” says Stéphane Aris-Brosou of the University of Ottawa in Canada.

However, while many of the mutations are linked to diseases, their effects are minor and it is unlikely that they are causing the people who have them …