Growing understanding of accumulating somatic mutations in healthy human tissues contributing to aging

Single-cell DNA and RNA sequencing made it possible to track the accumulation of somatic mutations during the lifetime of an organism. This emerging sub- discipline is explicitly called somatic evolution and it already delivered the result of showing how somatic mutant clones, harbouring cancer-associated mutations accumulate in the human esophagus with age, using only a handful of individuals (see Somatic mutant clones colonize the human esophagus with age by Martincorena et al.,2018). Somatic mutations accumulate in clonal hematopoiesis with age, similarly to the somatic evolution results mentioned earlier related to human esophagus. Bulk whole-exome DNA sequencing data from blood of more than 17,000 people showed this phenomenon, observed eg. in 18.4% of cases between 90-108 years of age, associated with increase in all-cause mortality and different cardiovascular adverse events (see Age-related clonal hematopoiesis associated with adverse outcomes by Jaiswal et al., 2014).

Now a research team at Stanford University has assembled what they call ambitiously ‘The somatic mutation landscape of the human body‘ from over 7500 tissue samples, representing 36 distinct tissues. This catalog contains over 280,000 mutations with an age range of samples being 20-70. The paper was published in Genome Biology and it is open access.