Parental age shapes how new genetic mutations are passed on, with fathers contributing more mutations overall, but older mothers showing unique patterns that cluster in specific genome regions, influencing long-term human genetic diversity and potentially affecting health across generations.
September 2017 – Nature
Key takeaways
- Fathers contribute most new mutations: The number of genetic mutations inherited from fathers increases sharply with age, about four times more than from mothers, due to continuous sperm cell division. This accumulation may influence offspring health and highlights the importance of paternal age in longevity-related genetic risk
- Maternal age affects mutation patterns: While mothers pass on fewer mutations overall, the types and locations of these mutations shift with age. Older mothers transmit more C>G mutations, especially in specific genome regions, highlighting a unique, age-related influence on genetic variation and potential age-related disease predisposition
- Mutation hotspots are maternally driven: Certain genome regions, notably on chromosome 8p, accumulate maternal mutations at rates up to 50 times higher than elsewhere. These hotspots suggest long-standing, sex-specific genetic processes that may influence evolution, ageing, and inherited disease risk more than previously appreciated
- Maternal clusters grow with age: Older mothers tend to pass on more clustered mutations that span longer DNA stretches compared to fathers. These clusters are enriched in specific regions, possibly due to structural stress in ageing eggs, revealing a novel mechanism linking maternal age to genetic ageing in offspring
Read the article at: Jónsson, Hákon, et al. “Parental influence on human germline de novo mutations in 1,548 trios from Iceland.” Nature, vol. 549, 2017, doi:10.1038/nature24018.
