This study intended to examine a set of 20 autosomal Single Nucleotide Polymorphisms
(SN Ps) selected from the 52-plex developed by the SN PforID Consortium for human
identification and to study its usefulness in investigation of paternity cases. We designed
two 10-plexes and investigated 50 paternity cases, previously examined in this laboratory
with standard ST R methodologies. There was a total agreement between exclusion and
not exclusion cases with the results obtained by ST R analysis, except for one case where
it was not possible to exclude the father with SN P analysis, probably due to the small
number of SN Ps studied. In paternity exclusions, between one and seven incompatibilities
were detected for the SN P loci studied. This study demonstrates that analysis of a small
number of SN P loci, as 20 polymorphisms, can be very useful in biological kinship
investigation as a complement to standard ST R methodologies, being an advantage to
increase the number of loci to strengthen SN P study as a complement methodology