The age at which people lose their virginity is, in part, influenced by their genes. Scientists have found genetic factors play a role in when a person first has sex, the age when puberty begins and when they have their first child.

A team of researchers from the University of Cambridge looked at over 125,000 people aged between 40 and 69 years (59,357 men and 66,310 women) to look at genetic differences influencing the timings of sexual behaviour. The participants were part of UK Biobank – a long-term study into the roles of genes and environment on health and disease.

It is known the age at which a person first has sex is influenced by social factors, including peer-pressure and family beliefs. Previous research has also shown having sex at an early age is linked with poorer mental and physical health, and lower educational achievements.

In the study, published in Nature Communications, scientists looked at the genetic data of the participants along with information on their sexual behaviours. They identified 38 gene variants associated with the age participants lost their virginity, including those involved in risk-taking.

'Substantial proportion' of variation down to genes

Several variants were found in genes previously linked with brain development and neural connections. The team also found associations with these genes and other behaviours, including the timing of the onset of puberty and the age a person had their first child. The authors replicated their findings in the genetic data in over 250,000 people who took part in the Women's Genome Health Study.

"Here we show that a substantial proportion of variation in AFS [first sexual intercourse] is due to genetic factors, which likely act through a variety of biological mechanisms, many of which influence either physical traits, such as puberty timing, or personality characteristics, such as risk-taking propensity," the researchers wrote.

Lead author John Perry said: "While social and cultural factors are clearly relevant, we show that age at first sexual intercourse is also influenced by genes which act on the timing of childhood physical maturity and by genes which contribute to our natural differences in personality types."

The team says understanding how puberty timing and personality influences sexual behaviours could be used to develop "targeted and more effective approaches to health education and promotion of safer health-related behaviours".