Analysis of Inheritance of Polymorphisms in the HV3 region of the mtDNA in mother/child pairs

Abstract

The analysis of mtDNA sequences has found great application in the human identification field, and the high number of mtDNA molecules found by cell increases the possibility of some copies to survive in degraded samples, allowing the genotyping of samples as bones, saliva, nails and hair. Important properties of mtDNA as the exclusively maternal inheritance, the absence of recombination and the high rate of mutation in the control region provide the high index of polymorphism, mainly in hipervariables regions HV1 and HV2. However, although highly polymorphics, one limitation to the use of these regions is the presence of many highly common polymorphisms, resulting in sequences (or haplotypes) common to more than one individual, or maternal lineages, in different populations. Thus, the use of additional mtDNA markers to the classic sequencing of HV1 and HV2 can increase the power of discrimination of common haplotypes and, therefore, of individuals. The main goal of this project is the analysis of polymorphisms in the sub-region HV3 of the mtDNA control region in pairs of mothers and children which could not previously be individualized and matched through the analysis of HV1 and HV2, in order to try to make this match, evaluating in this way the discrimination power of HV3. As by-product, we will identify the types and the frequency of the polymorphisms in HV3 region in the Brazilian population.