Revista de investigación forense

Alternative Silver Stain Detection protocol for the GenePrint® STR System Applied to Mestizo Population From Jalisco (West of Mexico)

Abstract

Rangel-Villalobos h, Salazar-Flores J, Muñoz-Valle JF, Torres-Jasso JH and Páez-Riberos LA

A population sample of 163 unrelated individuals from the Mexican state of Jalisco (West of Mexico) was PCRtyped with the Geneprint® STR System including nine autosomal STRs (CSF1PO, TPOX, TH01, F13A01, FESFPS, vWA, D16S539, D7S820 and D13S317). For this purpose, we implemented an alternative protocol for STR silver stain detection, which provides some economical and technical benefits: 1) make easy the gel handling; 2) simplify the process avoiding the use of some –toxic– reagents; 3) require lesser timer and made-in-home solutions; 4) the original gels can be dried and stored for re-analysis, if necessary. The allele frequencies estimated were similar to a previous report from the same Mexican population, which allowed pooling STR genotype data for upgrade the forensic parameter estimates (n= 472). However, this is the first –and unique– population study in Mexico for F13A01 and FESFPS; thus, the sample size did not increased for these loci (n= 163). In the studied population, genotype distribution by locus and two-loci combination was in agreement with Hardy-Weinberg expectations for all nine STRs. For the STR system, the power of discrimination (PD) and exclusion (PE) were >99.999% and 99.9%, respectively.