The signals of the genotyping results were clean and did not show stuttering bands. Micro-Checker showed no evidence of scoring error due to stuttering and large al- lele drop-out. The program did not identify any geno- typeing error due to null alleles either. Our test of geno- typing artifacts suggest that any deviation from Hardy- Weinberg equilibrium in our analysis is the result of change in allele frequency but not due to genotyping ar- tifacts.