Telomerase knockdown does not induce significant telomere shortening or telomere DNA damage-induced foci (TIFs) in the time frame of this experiment. (A) Cumulative frequency of telomere lengths measured by PNA intensity. (B) Telomeres detected per area. (C) TIFs detected per telomere measured by colocalization of γH2ax foci and PNA foci. (D) TIFs detected per γH2ax foci. (E) γH2ax foci detected per area. Statistical significance was assessed using 1-way ANOVA and Dunn’s multiple comparison test with a significance cutoff of P < .05 in Prism (GraphPad). NV, no virus.