LD block structure across NAT2 gene. The upper panel shows the location of 5 polymorphisms in NAT2 gene and lower panel shows the output of Haploview. LD plot where in each square (with D' values written within the box) represent a pairwise linkage disequilibrium relationship between the two SNPs. Squares indicate statistically significant LD between the pair of SNPs as measured by the D' statistic. Darker colours of grey indicate higher values of D', up to a maximum of 1 and white squares indicate pairwise D' values of < 1 with no statistically significant evidence of LD. The blocks generated under confidence interval algorithm of Haploview are marked. A: Afro-Brazilians, B: Whites and C: Amerindians.