Table 3.

Interethnic distribution of CYP2A6 alleles.

Population	CYP2A6*1A/B1	CYP2A6*2	CYP2A6*42	CYP2A6*5
Caucasian3	96.5–98.9%	2.3–3.0%	0.5–1.0%	0%
Chinese	83.8%	0–0.7%	15.1%	1.0%
Japanese4	about 80%	ND	about 20%	ND

¹Combined CYP2A6*1A and CYP2A6*1B.

²Combined CYP2A6*4A-D.

³Finnish, Spanish, Swedish, American.

⁴The data on Japanese is less complete than in Caucasian and Chinese populations.

ND, not determined.

Data compiled from [12, 40, 41, 43, 46].