Are you an early riser? Your DNA might be linked to Neanderthals

People who like going to bed early and waking up with the larks may have Neanderthal DNA.

The ancient primates passed on their “morningness” when they mated with our Homo sapiens ancestors around 70,000 years ago, scientists say.

This would have helped early humans from Africa adapt to the shorter days of the northern climate, where Neanderthals had lived for hundreds of thousands of years.

Epidemiologist John Capra, of the University of California in San Francisco, said: “By analysing the bits of Neanderthal DNA that remain in modern human genomes we discovered a striking trend.”

“Many of them have effects on the control of circadian genes in modern humans and these effects are predominantly in a consistent direction of increasing propensity to be a morning person.”

For the genome-wide association study, the scientists used data from UK Biobank, which holds genetic, health and lifestyle information on half a million people.

They discovered that some people have up to four per cent Neanderthal DNA, including genes linked to skin pigmentation, hair, fat and immunity.

These people were consistently early risers, the researchers said.

Prof Mark Maslin, of University College London, who was not involved in the study, said: “Now we have genetic evidence that some of us really are morning people. When humans evolved in tropical Africa, the day lengths were on average 12 hours long. Now hunter gatherers spend only 30 per cent of their awake time collecting food, so 12 hours is loads of time.”

“But the further north you go, the shorter the days get in winter when food is particularly scarce, so it makes sense for Neanderthals and humans to start collecting food as soon as there is any light.”

The findings were published in the journal Genome Biology and Evolution.