Older fathers more likely to pass on disease-causing mutations due to 'selfish' sperm stem cells
Older men are more likely to pass on disease-causing mutations to their children due to the faster growth of mutant cells in the testes with age.
Why it matters
- Older fathers have a higher risk of passing on disease-causing mutations.
- This risk increases non-linearly with age.
- Highlights the importance of paternal age in family planning.
By the numbers
- 1 in 50 sperm have a disease-causing mutation in men in their early thirties.
- This rises to nearly 1 in 20 by age 70.
- Over 40 genes identified with mutations that make sperm stem cells "selfish".
The big picture
- The increase in mutations is due to "selfish" sperm stem cells that proliferate more as men age.
- These mutations can lead to severe neurodevelopmental disorders and increased cancer risk.
- The body seems to protect testes from environmental factors like smoking and obesity.
What they're saying
- Experts confirm the increased risk and suggest considering sperm freezing or screening techniques.
- Comments highlight the lack of fertility advice for men and the impact of lifestyle factors.
Caveats
- The study is based on a sample size of 81 men.
- The findings are correlational and may not apply universally.
What’s next
- Further research on lifestyle interactions with genetic mutations.
- Potential for screening and preventive measures for older fathers.