MT-ND5 and leukemia: Additionally, an increased level of mtDNA damage was found in the ND5 region only in human leukemia cell lines: 2.9 lesion per 10 kb DNA (Rc NR extract) and 4.0 lesions per 10 kb DNA (Rc TR extract) in K-562 cells and 4.3 lesion per 10 kb DNA (Rc NR extract) and 4.6 lesions per 10 kb DNA (Rc TR extract) in CCRF-CEM cells (Figure 3).