RESUMO
X-chromosomal short tandem repeats (X-STRs) are useful for the identification of absent single parents and complex blood relations. In the present study, we aimed to identify novel STR loci for use as DNA markers by conducting polymorphism and haplotype analyses. We detected three novel STR loci (LC552061, LC552062, and LC552063, with repetitive structures of (GGAA)n(GGGA)m, (CCTT)n(CCCT)m, and (ATTT)n, respectively) in the p11.4 region of the X chromosome. For these X-STRs, the polymorphism information content values ranged from 0.5766 to 0.6377 and the power of discrimination in males and females ranged from 0.6269 to 0.6844 and from 0.8105 to 0.8537, respectively. The linkage disequilibrium analysis revealed p values of < 0.0001, < 0.0001, and 0.00909 between LC552061 and LC552062, LC552061 and LC552063, and LC552062 and LC552063, respectively. Additional linkage disequilibrium analysis including seven previously analyzed loci (LC149476, LC149479, LC149480, LC149484, LC317283, LC317284, and LC317285) revealed a p value of < 0.001 among each of the five loci (LC149476, LC149479, LC149480, LC149484, and LC317283) and between LC317284 and LC317285, indicating that they were a linked group. These results indicate that, in addition to the seven previously detected loci, the three novel X-STR loci identified in the present study might be useful DNA markers for complex kinship analysis and might support the Investigator® Argus X-12 kit.