Validation of the X-chromosomal STR DXS6809

This paper presents sequence and population genetic data of the microsatellite marker DXS6809 (GDB 365492) obtained from a German population sample ( n=725 chromosomes). DXS6809 is a highly polymorphic X-linked tetranucleotide polymorphism presenting 12 alleles in our population. Sequencing of 77 PCR products covering 12 alleles (by length), characterised DXS6809 as a marker with a complex repeat sequence structure. A polymorphism information content (PIC) of 0.825 and a mean exclusion chance (MEC) of 0.815 were obtained. A deviation from the Hardy-Weinberg equilibrium (HWE) could not be detected and male and female samples exhibited a similar allele distribution. Kinship testing revealed a typical X-linked inheritance and 2 mutations were found in 394 meioses. DXS6809 is located 90.18 Mb, i.e. 102.3 cM, from the Xp-telomere (Xp-tel), corresponding to Xq21.33. The presented data qualify DXS6809 as a useful supplement to the known forensic ChrX marker panel.