Mr Right or Mr Right Lifespan?

Researchers say we unwittingly choose partners with similar life expectancy and disease risks.

Scientists may be closer to an explanation for why long-term couples often die within weeks of each other.

Would you say it was your partner’s sense of humour that first attracted you? Perhaps their winning smile, or gym-honed physique? A study suggests you may in fact have been seduced by their genetic likelihood of keeping you company all the way till death do you part.

Researchers at the University of Edinburgh have found humans unwittingly appear to choose a partner likely to have a similar life expectancy.

We are also likely to select someone who shares similar risks of illnesses such as heart disease or high blood pressure.

“It has been known for about 100 years that the longevity of partners is similar, but I think until now the general understanding was that the reason why that was the case was because partners were sharing the same household and lifestyle for many, many years and that led to the same diseases and eventually to similar longevity,” says Albert Tenesa, who led the research. “What we have found in this research is that it is not that simple.”

Rather than looking only at couples, the experts looked at how similar sets of in-laws were to each other in terms of longevity and the diseases they had, using the UK Biobank, a repository of data on the genes and lifestyles of more than half a million people.

They found that the similarities for both life expectancy and conditions including Alzheimer’s, heart disease, stroke and lung cancer were greater than would be predicted by chance. “That indicates it is not just the households these couples share (that leads to similar life expectancies and risks of disease),” Tenesa says.

While some of the link might be down to people choosing partners from similar socioeconomic backgrounds, he says, it looked likely that genetics played a role.

For instance, people with genes that predisposed them to become smokers might be more likely to pair up with other smokers, raising their risk of lung disease, leading to similar life expectancies.

The findings are “another piece of the puzzle” to explain why long-term couples often die within weeks of one another, or suffer from the same ailments as they age.

The study was published in the journal Heredity.

The Times