Mahasneh et al. (2012) conducted a study in 49 (5 women and 44 men) lung cancer patients, 54 (26 women and 28 men) colorectal cancer patients and 99 (7 women and 92 men) cancer-free controls.  Using PCR-RFLP, the polymorphisms of NAT2 gene were screened.  Five types of the alleles were found, the wild type WT (NAT2*4) allele and the M1 (NAT2*5A), M2 (NAT2*6A), M3 (NAT2*7), and the M4 (NAT2*14A) polymorphisms caused by point mutations in the NAT2 gene.  While M2 polymorphism was apparent in the lung and colorectal cancer patients, significant difference was found in the distribution of rapid and slow acetylators genotypes between cancer-free controls and lung cancer patients, but not in the colorectal patients.  It was observed that individuals with rapid acetylators genotypes have a high risk of developing lung cancer but not colorectal cancer.

Bu et al. (2004) studied the frequencies of alleles and genotypes for CYP1A1, NAT2, GSTs, MTHFR, MTR (MS), and NQO*1 genes among Arabs.  Of the studied group, 95% were from Saudi Arabia, and 5% were from Jordan, Syria, Lebanon, and Yemen.  The mean age was 37 years, and male to female ratio was (25:1).  Of the major NAT2 gene alleles, the variant allele 5B had the highest frequency (41%), followed by 6A (22%), 4 (17%), 13 (6%) and 5A (4 %). The 5B/5B genotype was the most common among Arabs (22%), followed by 5B/6A (18%), and 4/5B (10%).

Al-Yahyaee et al. (2007) identified 12 polymorphisms in the NAT2 gene while genotyping 127 randomly selected unrelated northern Sudanese subjects. Four alleles coded for rapid acetylators (18%), and eight alleles coded for slow acetylators (82%). Two genotypes coded for rapid acetylation (4%), 10 for intermediate acetylation (28%), and 13 for slow acetylation (68%). The a.G191A African SNP and the a.G857A predominantly Asian SNP were each detected at a low frequency of 3%.