Table 2 The five phase-resolved NAT2 molecular data sets investigated.
From: Inferring haplotypes at the NAT2 locus: the computational approach
Population sample | Proportion of phase-unknown multiple heterozygotesa | NAT2 gene diversityb | Deviation from the Hardy-Weinberg equilibrium (exact p-value)c |
|---|---|---|---|
258 Spanish [45] | 66.7% | 0.65 | 0.012 |
137 Nicaraguans [30] | 59.1% | 0.70 | 0.072 |
112 UK Caucasians [24] | 52.7% | 0.69 | 0.222 |
101 Black South Africans [24] | 63.4% | 0.86 | 0.122 |
1000 Koreans [31] | 50.0% | 0.52 | 0.016 |
- All population samples were genotyped for the same seven nucleotide changes (G191A, C282T, T341C, C481T, G590A, A803G, G857A), except Koreans where the C190T mutation was investigated instead of G191A.
- aProportion of multiply heterozygous individuals with ambiguous genotype whose phase has been resolved molecularly.
- bExpected heterozygosities for the NAT2 haplotyped system were estimated as
where n is the number of gene copies in the sample, and pi is the sample frequency of the i-th haplotype. - cThe significance of deviations from Hardy-Weinberg equilibrium was tested for genotypic data with known gametic phase using the random-permutation procedure implemented in the Arlequin package [51]: a Fisher's exact test using a Markov chain random walk algorithm was performed for each data set. The resulting p-values were considered significant if inferior to 0.05 (significant p-values are shown in bold).
where n is the number of gene copies in the sample, and pi is the sample frequency of the i-th haplotype.