An unexcluded paternity case investigated with hypervariable DNA loci.

A paternity case involving a putative father, a child, and the mother was referred to our laboratory for testing. Parentage was not excluded with 23 kinds of standard blood group markers and HLA, but the putative father requested more-affirmative evidence of paternity. Seven kinds of DNA probes that recognize hypervariable loci were applied. On the basis of the allelic frequencies and their confidence intervals previously reported among unrelated Japanese individuals, as well as confirmed codominant segregation of the polymorphism, the exclusion probability and paternity index were calculated for this case. The cumulative paternity index from the seven DNA probes was 1.4 x 10(6), which was 316 times higher than that from the 23 standard blood group markers and HLA. Accordingly, DNA polymorphism is considered to be informative enough for paternity testing.