Thread by @dr_appie

The largest study on late life virginity, based on > 400k individuals, out now in @PNASNews

Open access link:

Shoutout to shared first author @laurawesseldijk ❤️

Thread below 👇🏽 pnas.org/doi/10.1073/pn…

Sex is central to human wellbeing.

~1% of people never have sex. While some people simply don’t want sex, for others, no partner can mean loneliness, lower wellbeing, or even economic disadvantage.

No sex is also interesting for genetics as it is an evolutionary “dead end”.

Sexless individuals reported:
- More loneliness, nervousness, unhappiness
- Fewer close relationships & social connections
- Less alcohol & drug use

Patterns differed by sex: for men, physical strength, income, and social connection mattered more.

Where you live matters too.

Men in regions with fewer women were more likely to be sexless.

Sexlessness was also more common in regions with higher income inequality.

Thousands of genetic variants with very tiny effects together explain ~15% of variation. The genetic correlation between men and women is .56.

Ancient DNA shows an allele significantly associated with sexlessness declined over 12,000 years, consistent with natural selection.

Genes linked to sexlessness overlap with genes associated with:
- Higher education & IQ
- Less substance use
- Higher autism & anorexia risk
- Lower ADHD, anxiety, depression & PTSD risk

Sexlessness is relevant to wellbeing and evolution. But it’s also a complex behavioral trait: its genetic associations trace back to many other traits and environments.

The associations we find are correlational and likely to be culture-specific, so more research is needed.

Many thanks to my co–first author @laurawesseldijk (🥰), co–last authors Brendan Zietsch & Karin Verweij, and all other co-authors ❤️

Check out the paper here: pnas.org/doi/10.1073/pn…

@laurawesseldijk Brendan Zietsch wrote a good and accessible summary of our paper here: theconversation.com/1-of-people-do…