In a study published today, scientists in Rotterdam claim for the first time to have found a gene that specifically affects how old people look. The gene came to light when researchers noticed that people who carried mutations in the gene appeared, on average, two years older than they were.
The work, if verified, could help scientists unpick at the molecular level how people’s faces change with time, and ultimately develop ways to slow down the most visible effects of ageing.
“This is the first gene we have found for perceived age, and this single gene has an effect of two years,” said Manfred Kayser, professor of forensic molecular biology at Erasmus Medical Centre in Rotterdam. “We know there are others out there. We are just at the beginning.”
Scientists have long known that people appear to age at different rates, and that genes and lifestyle are both involved. Smoking and too much UV from sunlight speed up skin ageing, but the genetics at work in looking old – or young – have so far proved elusive.
Working with scientists from Unilever, Kayser asked a group of observers to estimate the ages of nearly 3,000 people who had provided pictures of their faces and DNA for what is called the Rotterdam study. He found that people consistently rated women as being older than their years, and men as being younger. The finding might reflect the media’s obsession with images of young women, suggested one scientist who was not involved in the work.
But that was not the study’s main result. After scouring the people’s genomes, Kayser found that variations in one gene, called MC1R, were more common in those who looked old for their age. To check the finding, he repeated the search in two other groups of people, one in Netherlands, the other in the UK. The MC1R gene, which is responsible for red hair, cropped up again.
The scientists next looked at how the gene might be working. As well as producing red hair, the MC1R gene is responsible for pale skin. With pale skin comes more susceptibility to sun damage and wrinkles. But writing in the journalCurrent Biology, the scientists claim that the effect of the gene remained even when they ruled out skin colour, wrinkles, and sun exposure.
“There are two things we don’t know: what part of perceived age does it influence, and how does it do it,” said Kayser. As ever, more work is needed.
David Gunn, a scientist at Unilever, said that understanding why some people look young for their age could help the company develop products to keep people “younger looking for longer.” But Unilever is not a drugs company, and any product that intervened with the ageing process on the genetic level would likely be classed as a drug, and require clinical trials and approval from national regulators before it would be allowed on the market.
But Kayser said the work has implications beyond face creams and other cosmetics. “By finding more genes involved in perceived age, we can better understand the relationship between how old you look and how healthy you are,” he said. “It is a different approach to understanding healthy ageing.”
Ian Jackson, a geneticist at Edinburgh University, said it was hard to know whether the scientists had properly ruled out the role of skin colour. If MC1R affects how old people look through its effects on skin – with paler people looking younger – the results are far less intriguing. Another question also comes up when people are asked to rate the age of others. “Are you really measuring how old people look, or are you measuring the psychology of the observer?” he said.
Julia Newton-Bishop, professor of dermatology at Leeds University, said that while the scientists rule out the effect MC1R has on skin’s resistance to sun rays, it was difficult to rule this out. “It is true that MC1R does have many complex effects on skin cells, but I don’t think that the study establishes additional mechanisms,” said said. “It merely suggests that the effects may not all be related to the sun.”
João Pedro de Magalhães, who studies the genetics of ageing at Liverpool University, said the study was “fascinating”.
“MC1R has been genetically associated with UV-induced skin damage, skin features like pigmentation, freckles and age spots, and with skin cancer. So it is perhaps not surprising that this gene plays a role in perceived age,” he said. “I suspect larger studies will uncover many other genetic variants and this is only the beginning for this line of research. This could certainly open up new research directions for exploring clinical applications by targeting MC1R. As I am sure you are aware, there is a massive cosmetics industry focused on anti-ageing.”