Sequence analysis of alleles at a microsatellite locus D14S299 (wg1c5) andpopulation genetic comparisons

In order to increase the discriminating power of DNA analysis in personal i dentification, we evaluated the forensic-utility of the microsatellite locu s D14S299 (wg1c5) in the Japanese population and also in the Chinese and Ca ucasian populations. Twelve differ-ent alleles were identified in length by gel electrophoresis with silver staining. The major alleles in Japanese we re sequenced and designated as the numbers of the variable repeats (CGAT or GGAA). There were five variable regions and extensive homoplasy was found. However, the allele fragment lengths were in 4 bp increments and no "inter alleles" were found. The estimated heterozygosity and the polymorphism info rmation content (PIC) were 0.726 and 0.689, respectively in Japanese. Those in Chinese (0.743 and 0.704) were similar to those in Japanese, while thos e in Caucasians (0.812 and 0.781) were much higher. After adjacent alleles were combined to yield at least five entries, statistical analysis was perf ormed. The power of discrimination (PD) was 0.887 in Japanese, 0.895 in Chi nese and 0.935 in Caucasians and no significant deviations from the Hardy-W einberg equilibrium were found in the three populations. We retyped all app arently homozygous samples using an alternative pair of flanking primers an d found them to be true homozygotes. D14S299 appears to be a useful STR loc us for forensic practice.