Characterization of the Philippine Y STR population involving 23 LOCI: Population information, mutation analysis and forensic assessment

• Main Author: Tabulina-Angustia, Shiela Marie
• Format: text
• Language: English
• Published: Animo Repository 2014
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4599
• Institution: De La Salle University

Y- chromosomal STR markers have shown to be advantageous in analyzing male DNA in mixtures containing high female DNA fraction and as supplementary markers for paternity testing. To be useful in the Philippine population, markers must first be evaluated for its variability and mutability. In this study, twenty-three Y- chromosomal STR markers were used in characterizing the Philippine male population. Haplotype and allele frequencies were determined in 629 unrelated Filipino males while mutation data were gathered from the analysis of 133 confirmed father and son transmissions. A haplotype diversity of 0.99992 with a standard error of 0.00230 was obtained. This defines the presence of 612 haplotypes from the sample of 629 individuals. Out of the 612 haplotypes, 596 haplotypes were found to be unique, 15 haplotypes were found to be shared by two individuals and 1 haplotype was shared by three individuals. The discrimination capacity was calculated to be 97.30%. Among the 3,059 meiotic transfers covered, 11 mutations were recorded with an average overall mutation rate of 3.59 x 10-3 in the population. Five mutations resulted in a gain of repeat and 6 resulted in a loss of repeat suggest the absence of neither expansion nor contraction bias. DYS635 locus with three mutational events has the highest mutational rate (2.26x10-2 (95% CI (4.7-64.5) x 10 -3) across all loci. A haplotype with a duplicated allele in both father and son were observed at the DYS576 locus while an individuals haplotype was found to contain four alleles at DYS385 A/B. In addition a variant of DYS456 was observed to fall outside the marker range and a microvariant was observed at DYS576. Information obtained from this research verified the usefulness and informative power of having additional markers for routine casework.