Mitochondrial DNA and aging: Study on heteroplasmy levels with DHPLC technology within the EU project MARKAGE

The two hypervariable segments (HVS-I and HVS-II) of mitochondrial DNA (mtDNA) control region were sequenced for a population of 208 unrelated healthy individuals sampled from Suiping County, Henan Province, China. A total of 192 different haplotypes were identified, of which 179 haplotypes were unique (93.23%). The variation of the mtDNA HVS-I and HVS-II was confined to 166 nucleotide positions, of which 115 were observed in the HVS-I and 51 in the HVS-II. The haplotype diversity and random match probability were 0.9991 and 0.0061, respectively. Following the principle of the updated East Asian mtDNA phylogeny tree, individual samples were assigned to the specific haplogroups based on the information both from control region and coding-region obtained. Haplogroup D was the most common haplogroup (25.96%). The northern China-prevalent haplogroups (A, C, D, G, M8, Y, and Z) and the southern China-prevalent haplogroups (B, F, M7, N9, and R9) accounted for 48.56% and 46.63%, respectively, of the Henan Han mtDNA gene pool. The mtDNA hypervariable region was highly polymorphic in Henan Han population. These sequences could serve as mtDNA reference data for forensic casework in Henan population as well as for population genetic study.