Arthritis sufferers can blame it on Ice Age man

FOR the 10 million Britons suffering from arthritis, it may be cold comfort, but they may not be alive today were it not for their aching limbs.

Researchers have discovered that a gene mutation that increases the risk of arthritis evolved during the most recent Ice Age to help protect our ancestors from frostbite.

Around half of all Europeans carry a variant of the GDF5 gene, which nearly doubles the chance of developing painful joints, and also reduces their height by approximately 1cm.

Although it may seem like an evolutionary disadvantage to be shorter and less mobile, in fact it helped early humans to ward off the freezing temperatures of the north as they ventured out of Africa around 50,000 years ago. Being short and stocky helped our ancestors withstand the bitter cold and reduced the risk of life-threatening bone fractures when slipping on ice.

And because arthritis usually appears after reproductive age, it would not have proved detrimental to starting a family, so the mutation was passed on. Dr David Kingsley, professor of developmental biology at Stanford University, said: “This gene variant is present in billions of people, and it’s likely responsible for millions of cases of arthritis around the globe.

“Many people think of osteoarthritis as a kind of wear-and-tear disease, but there’s clearly a genetic component at work here as well.

“It’s possible that climbing around in cold environments was enough of a risk factor to select for a protective variant even if it brought along an increased likelihood of an age-related disease like arthritis.”

Researchers first linked a mutated form of GDF5 to arthritis and height in the Nineties. They discovered it was being controlled by genetic machinery which tells the gene to turn off bone growth. In the new study they looked at people who submitted their DNA for the 1,000 Genomes project and noticed that the gene variant was more common in Europeans, but rare in Africans.

The research was published in the journal Nature Genetics.