Heteroplasmy in the metastatic VM-M tumor cell line. Mitochondrial 16srRNA revealed a heteroplasmic mutation at position 2159 of an A to G transition. The three VM brain mitochondrial populations (LM, HM, and FM) displayed the same chromotagraph profile. The same level of heteroplasmy was observed in duplicate independent samples for the VM-M cell line. Arrow indicates heteroplasmic nucleotide at position 2159 compared to control.