Table 4. NAT2 genotype-assigned phenotype frequencies (%) in different regions of the world.

Region	Subjects (n)	NAT2 acetylator status based on genotyping
		Slow acetylators	Intermediate acetylators	Rapid acetylators
Europe (Caucasian)	5,382	58.0 (9.0)	34.0 (6.0)	8.0 (9.0)
Africa	1,034	46.0 (19.0)	40.0 (14.0)	14.0 (14.0)
Asia	1,790	45.0 (20.0)	37.0 (13.0)	18.0 (19.0)
Middle and South America	0824	27.0 (18.0)	52.0 (15.0)	21.0 (16.0)
East Asia (Chinese, Korean, and Japanese)	2,062	14.0 (5.0)	46.0 (7.0)	40.0 (8.0)
Korean [65]	1,000	0009.6	0046.9	0042.8

Slow alleles (S)=NAT2^*5, ^*6, ^*7 and ^*14; Rapid alleles (R)=NAT2^*4, ^*12 and ^*13.

NAT2 acetylator status based on genotyping: slow acetylators=S/S, intermediate acetylators=R/S, rapid acetylators=R/R.

Data are expressed as means (SD).

Data taken from [41,70].