Computer simulation of clonal hematopoiesis arising under neutral drift. The graph shows the proportion of simulations producing more than 20 observable mosaic somatic mutations with a VAF less than 0.2 as a function of subject age, for different choices of N, the size of the active HSC compartment. The value of p, the probability that an HSC division will produce 2 daughter stem cells, was set at 0.25.⁵¹  Other parameters were fixed at λ = 1 division per 40 weeks,⁴³  mutation rate µ = 6.4 × 10⁻¹⁰ per base pair per division.⁵²