ABSTRACT
Definition about mutation rates of short tandem repeats (STRs) loci used in forensic analysis are useful for the correct interpretation of resulting genetic profiles and the definition of criterions for exclusion in paternity testing. Germline mutation of 14 STR loci was studied for 54,105 parent-child allelic transfers from 2575 paternity testing cases carried out during 2000-2007 from the Pernambuco State, Northeast Brazil. The parenthood in each of these cases was highly validated (probability > 99.99%). We identified 43 mutations at 12 loci. Locus-specific mutation rate estimates varied between 2 x 10(-4) and 2 x 10(-3), and the overall mutation rate estimate was 8 x 10(-4). Mutation events in the male germline were more frequent than in the female germline. The majority of the mutations could be explained by losses or gains of one repeat unit and there was no evidence for selection between insertion or deletion changes. Our data were compared with those of Portuguese and North-American populations for CSF1PO, D18S51, D21S11, D7S820, TH01, TPOX and demonstrated, despite the great difference in the size of the sample, that mutation rates of STR loci in a mixed population do not differ from that encountered in different populations.
Subject(s)
Genetics, Population , Microsatellite Repeats/genetics , Mutation , Population Groups/genetics , Alleles , Brazil , Child , DNA/blood , DNA/genetics , DNA/isolation & purification , DNA Fingerprinting , Female , Forensic Medicine/methods , Genetic Markers , Genotype , Geography , Germ-Line Mutation , Humans , Kinetics , Male , Mutagenesis, Insertional , Nucleic Acid Amplification Techniques/methods , Paternity , Reproducibility of Results , Sequence Analysis, DNA , Sequence Deletion , Templates, GeneticABSTRACT
As part of a long-term project on Northeastern Brazilians, population genetic data were obtained from 323 unrelated individuals from the state of Paraíba. The loci studied were CSF1P0, TPOX, TH01, vWA, D16S539, D7S820, D13S317, D18S51, D21S11, D8S1179, F13A01, F13B and LPL. Their distributions are in Hardy-Weinberg equilibrium. Forensic parameters were calculated and a comparison was made with geographically nearby populations.