TINF2 disruption at exon 2 in donor and patient HSPCs. (A) Telomere length analysis of colonies plotted by genotype at TINF2 exon 2. Mann-Whitney test. NS: P > .05. (B) Percentages of frameshift alleles of bulk hCD34⁺ cells before and after engraftment in NBSGW mice. Error bars indicate data point ranges of 2 biological replicates. (C) A schematic of the patient TINF2 locus with c.905_907delAGCinsGGTCATAT mutation (left). Lymphocyte telomere length (kb) according to age in the patient (right, brown dot). (D) Allele distributions of the patient CD34⁺ cells 5 days after nucleofection.