mtDNA haplotypes a powerful tool in anthropology and crime detection

Human mitochondrial DNA (mtDNA) contains 16,569 nucleotide and changes in mtDNA HVSI region occur 10 times faster than genomic DNA. The aim of this study was to assess polymorphism, the rate of mutation, homoplasy, frequency of haplogroups, haplotype variance and nucleotide diversity in HVSI region of mtDNA of Iranian ethnic groups. Blood samples were randomly obtained from 357 native non-relatives Fars, Azerbaijani, Gilaki, Kurdish, Baluch, Sistani, Turkmen and Arab volunteers. mtDNA was extracted and amplification of HVSI region was carried out. Automated DNA sequencing was carried out on a DNA Sequencer (ABI 310). The sequences were aligned based on the Cambridge reference sequence by Clustalx program and mutations and polymorphisms were determined. Haplogroups were determined according to mtDNA phylogenetic tree. Highest and lowest homoplasy was observed in Fars people (40%) and Sistani people (13%) respectively. The lowest nucleotide diversity among all studied ethnic groups belonged to Fars people and it was 0.862. Haplotype variance was 0.87 in Sistani people which was the highest. The most common haplogroup among different ethnic groups was HV. Frequency of mtDNA unique haplotypes among different ethnic groups is higher than that of a single ethnic group. Lower nucleotide diversity in one of ethnic groups demonstrates that they do not marry people with different ethnicities. Higher variance of haplotypes in other ethnic group indicates the importance of mtDNA in detecting their identity in criminal cases. Higher mutations in one of ethnic groups demonstrate that they are the most ancient ethnic group in Iran.