Moreover, differentiated tumours with short telomeres were significantly more positive for the nuclear immunostaining of the proliferation marker Ki‐67 than those tumours with normal telomere lengths (2‐tailed Mann–Whitney test p < .0001) (Figure 3D), supporting the replicative‐dependent shortening of the telomeres in thyroid tumours. The gene discussed is MKI67; the disease is thyroid tumor.