HVIII discrimination power to distinguish HVI and HVII common sequences

Abstract The mtDNA sequence analysis has been found important applications in the human identification field, and important properties as the exclusively maternal inheritance, the absence of recombination and high rate of mutation provide a high index of variability, mainly in hypervariable regions HVI and HVII. Although highly polymorphic, the presence of many highly common polymorphisms, resulting in sequences (haplotypes) common to more than one individual, is a limitation to the use of these regions in some cases. The use of additional mtDNA markers to the classic sequencing of HVI/HVII can increase the discrimination power of common haplotypes and, therefore, of individuals. Herein, we analyzed polymorphisms in mtDNA HVIII region in 19 pairs of Brazilian mother/child who could not previously be individualized and matched through the analysis of HVI and HVII, in order to try to make these matches, evaluating the discrimination power of HVIII. After HVIII analysis we were able to differentiate 4 pairs out of 19 (21%). Two mothers and two children presented the haplotype 16182C 16183C 16189 16217 16249 16312 16344 73 152 263 271 309.1C 315.1C, and could be distinguished in two pairs with HVIII sequences 460C 499A and 499A, respectively. Other 2 pairs showed rCRS 263 309.C 315.1C in HVI/HVII and could be matched later since one pair presented HVIII 477C polymorphism and the other showed 523D 524D sequence. In conclusion, about one-fifth of the cases could be distinguished by HVIII polymorphisms, being a useful additional analysis in some cases.