False paternity with one or two mismatches using commercial STR kits

Abstract

This study presents a case of false paternity where one or two mismatches were found by using three commercial STR kits. The analysis with the Identifiler kit yielded two mismatches at the loci D2S1338 and vWA. These data did not, however, enable us to exclude the alleged father, as the total number of excluding loci was less than three. Further STR loci were therefore employed to resolve the case. The PowerPlex 16 system yielded only one mismatch at the vWA locus previously found with the Identifiler kit. GenePhile G-Plex, on the other hand yielded two inconsistencies at D3S1744 and D18S536 (out of 15 loci in total). Since the disputed child was a female and we were not able to exclude the possible involvement of a close male relative, we choose to use Genephile X-Plex kit to finally resolve the case. Out of 13 loci tested, we found a complete match of the child's profile with the mother and eight mismatches with the alleged father, clearly indicating that the alleged father is not the biological father. This case emphasizes the usefulness of either Y-chromosome or X-chromosome DNA data for interpreting borderline paternity cases.

Keywords:

• paternity
• locus
• X-chromsome
• genotype
• STR marker