(A) Haplotype frequencies in the 28 samples genotyped for all seven common SNPs at NAT2 (i.e., without missing data), taken from the worldwide genotyping survey. Single populations are reported on the left side of the plot, with population codes in brackets; geographic areas are indicated on the right side, as follows: SSAFR, sub-Saharan Africa; NA, North Africa; EUR, Europe; CSASIA, Central/South Asia; EASIA, East Asia; AME, America. Only haplotypes with frequencies > 5% in at least one geographical region were represented individually; all other haplotypes were pooled into a single group (in white). Also, haplotypes NAT2*14A and NAT2*14B were pooled into the NAT2*14 cluster. (B) Median-joining networks of the inferred NAT2 haplotypes within three geographical regions: sub-Saharan Africa, Europe, and East Asia. Only haplotypes with frequencies > 0.005 within a geographic area were considered to construct the networks. Circle areas are proportional to the haplotypes' frequency, and branch lengths are proportional to the number of mutations separating haplotypes. Haplotypes' labels are shown in black; mutations are shown in red on corresponding network branches.