Population genetic evaluation of eight X-chromosomal short tandem repeat loci using Mentype Argus X-8 PCR amplification kit.

The evaluation of four pairs of X-chromosomal short tandem repeats (STRs), i.e. DXS10135-DXS8378, DXS7132-DXS10074, HPRTB-DXS10101 and DXS7423-DXS10134 was carried out using the Argus X-8 Multiplex amplification kit. These eight STRs are distributed as four closely linked pairs over the entire X-chromosome (ChrX), and for practical reasons they are assigned to four linkage groups 1-4. The genetic distance within the STR pairs is assumed to be <1cM, whereas the pair to pair space is about 50 cM or more. Here, we present single STR allele frequencies, haplotype frequencies of the respective STR pairs and further population genetic parameters of forensic interest. Most data refer to a German population, however small samples from Ghana and Japan were also investigated. Furthermore, sequencing of all STR loci displayed the presence of microvariant alleles and variations in the repeat flanking region. A total of 350 meioses investigated here revealed only one sperm DXS7132 mutation. For analysis of linkages within the STR pairs a study involving 104 female meiosis with respect to recombination events was performed. The STR panel presented here provides a powerful tool for solving complex kinship in the case that X-chromosomal lineages can be taken under investigation.