Development of two hexaplex systems with X-STR loci and their allele frequencies in Koreans

X-chromosomal short tandem repeat (X-STR). markers can be used to determine paternity in deficiency paternity cases with a female child(s) and in other kinship tests. In the present study, we established two X-STR hexaplex PCR systems. One set includes DXS6789, DXS6810, DXS7132, GATA172D05, DXS7423, and ARA, while the other set includes GATA165B12, DXS981, DXS6797, DXS9898, DXS8377, and DXS7424. These STR loci were genotyped in a Korean population (149 males and 121 females), and the allele frequency was obtained using the established multiplex PCR reactions and an automatic sequencing analyzer. None of the loci in female samples deviated from Hardy-Weinberg equilibrium. The combined probabilities of match (PM) calculated from 12 X-STR loci were 2.04 x 10(-12) in females and 7.46 x 10(-8) in males, which is highly informative. The high polymorphism of these X-STRs indicated the suitability of their use in kinship tests, and both hexaplex systems mill be used directly to analyze forensic cases.