Volume 47, Issue 4 (July 2002)
Population Data on Nine STR Loci in an El Salvadoran (Central American) Sample Population
Blood samples were obtained by venipuncture from unrelated individuals (n = 323) living in El Salvador. Approximately 1–3 ng of DNA were used in each PCR. The samples were amplified using the Profiler Plus™ kit (PE) and the alleles were separated and detected using an Applied Biosystems ABI310 genetic analyzer. The frequency of each allele for each locus was calculated from the numbers of each genotype in the sample set (i.e., the gene count method). Unbiased estimates of expected heterozygosity were computed as described by Edwards et al. (1). Possible divergence from Hardy-Weinberg expectations (HWE) was tested by calculating the unbiased estimate of the expected homozygote/heterozygote frequencies (1–4) and the exact test (5), based on 2000 shufflings experiments. An interclass correlation criterion (6) for two-locus associations was used for detecting disequilibrium between the STR loci. The program for this analysis was kindly provided by R. Chakraborty (University of Texas, School of Biomedical Sciences, Houston, TX).