Three polymorphic X-chromosomal STR markers within a 79 kb region at Xq28 were studied and registered in the GDB as DXS10146, DXS10134 and DXS10147. These markers were molecular characterised and evaluated for their forensic usage. As a result DXS10134 was recently integrated in the commercial available test kit Mentype Argus X-8. At locus DXS10146 we found 23 alleles with PIC and HET values of 0.878 and 0.887. Locus DXS10134 showed 17 alleles with PIC and HET values of 0.844 and 0.858. At locus DXS10147 only 5 alleles with some lower PIC and HET values of 0.636 and 0.692 were found. Additionally, the already known and closely linked STR DXS7423 was included into the haplotyping and recombination studies. Testing this cluster a German population of 404 males revealed the presence of 311 haplotypes. Recombination analysis was performed in 109 father-daughter-grandson trios in which two crossing over events were observed located in the 65.8 kb region between DXS10146 and DXS10134. By using this STR complex for haplotyping in kinship testing further genetic analyses are required to establish an exact recombination rate.