A case study of SNPSTR efficiency in paternity testing with locus incompatibility.

Instead of testing the additional STR loci, SNPSTR was included in the paternity testing for an alleged father-son duo case, with one inconsistency at the CSF1PO locus. We have chosen CSF1PO STR and five closely linked SNPs rs10077461, rs2569076, rs2228422, rs3733673 and rs3829987 to establish the SNPSTR and examined its potential use in paternity testing. A total of 152 haplotypes from 76 unrelated individuals were obtained by the nested-AS-PCR and 60 SNPSTR haplotypes were observed. The discrimination power of the SNPSTR haplotype was greater than either the STR or SNP haplotype alone. Its SNP part could be used to distinguish fathers from uncles. When SNPSTR was introduced into the calculation of parentage statistics, the paternity probability increased to 99.998%. Based on our findings, we concluded that SNPSTR could be considered a useful tool in forensic science.