,15,16 Therefore, in this study, the NAT2 genotyping of Brazilian patients undergoing TB therapy was carefully performed by the Sanger sequencing method to investigate whether the individuals with slow acetylator phenotype and homozygous genotype present a distinct risk of developing DIH when compared to the compound heterozygous genotype carriers, and thereby contribute to the advancement of precision medicine. The gene discussed is NAT2; the disease is tuberculosis.