PopGen Hwe Test

Test Hardy-Weinberg equilibrium for a biallelic locus given observed genotype counts (AA, Aa, aa). Computes allele frequencies, expected genotype counts under HWE, chi-square statistic with 1 df, and p-value. Reports whether the locus is in HWE (p > 0.05) and, if not, whether heterozygote excess or deficit is observed. Useful for detecting selection, inbreeding, assortative mating, or genotyping error at individual loci.