BCL2 restores cell-cycle quiescence and limits DNA damage in NHD13 progenitors. (A) Cell-cycle distribution (G₀, G₁, and combined S/G₂/M) of LKS cells from WT (n = 6), NHD13 (n = 4), BCL2 (n = 5), and NHD13/BCL2 (n = 5) mice (* indicates G₀P < .05 difference from WT). (B) Cdkn1a mRNA expression in LK cells from 3 mice of each genotype. (C) FACS quantification of γH2AX levels in nonapoptotic (caspase-3–negative) LK cells from 3 mice of each genotype (NS indicates P > .05; *P < .05).