Forensic Parameters and Genetic Variation of 15 Autosomal STR Loci in Mexican Mestizo Populations from the States of Yucatan and Nayarit

ABSTRACT

Allele frequencies and six forensic parameters for autosomal short tandem repeats (STR), as well as the genetic structure in two Mexican mestizo populations were determined. A total of 356 unrelated individuals from the states of Yucatan, at Southern Mexico (N=120) and Nayarit at Pacific Coast (N=236) were PCR-typed for 15 STR loci using the Power Plex 16 Promega kit. Genotype distribution per each locus was in agreement with Hardy-Weinberg expectations for the 15 STR in both populations. Penta E and FGA were the STR with the highest heterozygousity index, 0.8893 in Yucatan, and 0.9057 in Nayarit. Penta E also showed the highest power of discrimination in both populations, with 0.972 in Yucatan and 0.980 in Nayarit. For both populations, the combined power of exclusion and power of discrimination were higher than 0.9999999. Based on a principal component analysis, Yucatan and Nayarit were located between Spain and Mexican indigenous populations (Mayas from Campeche and Yucatan). Both populations were located in two separate clusters, suggesting different genetic structure. Our report contributes with STR data in Mexican populations, specially the allele frequencies for Penta D and Penta E in Yucatan and provides population data in Nayarit where no STR database was available.