The DIS80 and VWA loci were studied in a Karen population from Northern Thailand by the polymerase chain reaction and polyacrylamide gel electrophoresis. Twelve DIS80 and six VWA alleles were found. No deviations from the Hardy-Weinberg and linkage equilibrium were observed. The power of exclusion (PE) from the analysis of the DIS80 and VWA locus is 0.67 and 0.45, respectively, the power of discrimination (PD) is 0.95 and 0.85, respectively, with a combined PD of 0.99 and PE of 0.82.