Melinda Mills , University of Oxford
David Brazel, University of Oxford
Nicola Barban, University of Essex
Felix C. Tropf, University of Oxford
The onset of age at first sex (AFS) and first birth (AFB) is influenced by social and genetic factors. We exploit recent results of a genome-wide association study (GWAS) of AFS (N=387,338) and AFB (N=542,901), identifying 271 (AFS) and 88 (AFB) genetic loci that together accounting for up to 6% of the total explained variance. We find a strong genetic overlap of AFS and AFB with infertility traits (miscarriage, age at menarche and menopause), and early timing linked with psychiatric disorders (ADHD, major depression) and risky and additive behaviour (risk, smoking and cannabis use). We then move from correlation to causation using bi-directional Mendelian Randomization (IV) and Genomic structural equation modelling to unpack a complex network of mutual causation. Finally, we show that later AFS and AFB is a causal predictor of late-life health and longevity.
Presented in Session 119. Health and Fertility