Development of the X-linked tetrameric microsatellite marker HumDXS6789 for forensic purposes.

This paper presents sequence and population genetic data of the X-linked DXS6789 short tandem repeat (STR). The tetranucleotide repeat polymorphism DXS6789, also known as CHLC.GATA31F01, is located at the Xq22.3 region. This locus is unlinked with DXS6807 and slightly linked with ARA, DXS9898 and HPRTB. In kinship testing, DXS6789 is suitable for concomitant use with DXS6807. Population genetic data were obtained by analysing 250 unrelated males and 315 females from East Germany. In this population, the STR exhibited 12 clearly distinguishable alleles ranging from 154 to 198bps in length. DXS6789 is characterised by the following data: polymorphic information content (PIC)=0.70; observed heterozygosity (Het)=0.78; mean exclusion chance (MEC)=0.70. A deviation from the Hardy-Weinberg equilibrium could not be detected. The investigations we performed in 243 mother-child and 161 father-child meioses did not reveal any mutations.