With age the proportion of Tet2 mutant cells increases possibly bc the increased #inflammation that occurs with age contributes. Darwinian evolution happens in the bone marrow and stem cells with Tet2 mutations can outcompete ( replicate more, make more white blood cells) than those without (5/n)

We investigated whether Tet2 mutant stem cells could outcompete others in the presence of the inflammatory cytokine TNF, which increases with age. We put a mix of normal and Tet2-/- stem cells into old mice that had lots of TNF and those with none (TNF KO). 6/n