Genetic diversity of HLA system in a population from Guerrero,Mexico

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 144 Mexicans from the state of Guerrero to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes in the state of Guerrero include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Guerrero are Native American (61.36 ± 2.69% by ML; 54.17% of Native American haplotypes) and European (35.01 ± 4.59% by ML; 32.29% of European haplotypes), and a relatively low African genetic component (3.63 ± 2.38% by ML; 5.90% of African haplotypes).     

Forensic parameters and admixture in seven geographical regions of the Guerrero state (South,Mexico) based on STRs of the Globalfiler® kit

Background: New commercial STR kits have emerged with greater numbers of markers, which allows for obtaining stronger conclusions in forensic casework, which has been poorly studied in Mexico.

Aim: To obtain forensic parameters and to analyse the genetic relationships, structure and admixture in seven geographic regions of Guerrero state (South, Mexico) based on the Globalfiler^® kit.

Subjects and methods: A total of 245 unrelated Mexican individuals from seven regions of the state of Guerrero were analysed with the Globalfiler^® kit. Forensic parameters, pairwise comparisons, genetic distances, structure analysis and admixture levels were estimated.

Results: Allele frequencies and forensic parameters of 22 STRs were estimated in this Mexican population sample. The combined power of exclusion and power of discrimination values were > 99.9999% and >99.99999999%, respectively. The Native American, European and African ancestries estimated in the Guerrero state population were 70.9%, 25.9% and 3.2%, respectively.

Conclusion: Forensic validation of the Globalfiler^® kit was performed in the Guerrero state population. The geographic isolation level seems to be the principal factor in defining genetic relationships and admixture among the Guerrero sub-populations. Despite the intrinsic limitations of STRs for admixture analysis, these results are very close to previous values based on AIMs and genome-wide SNPs.