Table 2.

CYP2A6 allele nomenclature.

Allele	Nucleotide change	Trivial name	Effect	Enzyme activity
CYP2A6*1A	none			normal
CYP2A6*1B			gene conversion in 3′ flanking region	normal
CYP2A6*2	479T > A	v1	L160H	absent
CYP2A6*3	2A6/2A7 hybrid	v2	?	?
CYP2A6*4A	gene deletion	CYP2A6del	deletion	absent
CYP2A6*4B	gene deletion	d-type	deletion	absent
CYP2A6*4C	gene deletion	e-type	deletion	absent
CYP2A6*4D	gene deletion		deletion	absent
CYP2A6*5	1436G > T		G479V	absent

Source: http://www.imm.ki.se/CYPalleles.