A surprising role for human genes has been unveiled after conducting a DNA study on more than 380,000 people.

The study helped in finding the human genes, determining the age at which one would have their first sex.

Family stability, peer pressure, personality type and several other factors influence the teenagers from engaging into sex, at the earlier age or abstain until adulthood.

As per the research conducted by co-author Ken Ong of the Institute of Metabolic Science at the University of Cambridge, a huge gene trawl has revealed that, “genes have a substantial influence”.

He said, “Genetic factors explain around 25 percent of the differences in the age when people start to have sex”.

The genes likely influence such factors as the age at which puberty hits, and whether or not you posses a risk-taking personality.

Also read: BPH treatment can ruin your sex life, says study

According to the researchers, the average age of sexual maturity for both genders has decreased from about 18 years in 1880, to 12.5 in 1980.

Changes in nutrition and the larger physical size of children today, and also exposure to hormone-disrupting chemicals are majorly blamed by the scientists.

In a British health study, Ong and a team analysed the genes of more than 125,000 participants and noted an association between 38 gene variants and the age at which they first had love-making.

The research team further cross-checked this with gene datasets for 241,000 people in Iceland and 20,000 in the US, for a total sample size of over 380,000 people.

“We found that the size of the influence of genetic factors remained constant across decades of growing up, from the 1950s to the 1980s -- this shows that genetic factors are relevant across a wide range of cultures and social attitudes,” Ong said.

A few of the gene variants were also linked to other reproductive traits such as  age at birth of one's first child, and the number of children borne, they found.

Poor physical and mental health and also under performance at school are other significant reasons for having sex at a young age, a previous research said.
 
Early onset puberty has been linked to a higher risk for diabetes, heart disease and some cancers. Most of the researches till date has focused more on the socio-cultural causes for the teenage sex.

The team said it hoped the findings will help identify and help children more prone, genetically and otherwise, to engage in risky behavior.

By Phani Ch