These variants interact with environmental factors, such as socioeconomic status and when you were born, and are predictors of longevity and later life disease. In the largest genomic study conducted to date, they combined multiple data sources to examine age at first sex (N=387,338) and birth (N=542,901) in men and women. It was incredible to see that the genetics underlying early sex and fertility were related to behavioural dis-inhibition, like ADHD, but also addiction and early smoking. We found particularly strong links between early sexual debut, ADHD and substance abuse, such as early age at smoking. We hope our findings lead to better understanding of teenage mental and sexual health, infertility, later life disease and treatments to help.’
