Table 1.

CYP2E1 alleles (www.pharmvar.org/gene/CYP2E1) (accessed 11 December 2019)

Allele	Protein	Nucleotide changes, Gene	Effect	Enzyme activity
CYP2E1*1A	CYP2E1.1	None		In vivo	In vitro
CYP2E1*1B	CYP2E1.1	9896C>G		Normal	Normal
CYP2E1*1C	CYP2E1.1	6 repeats in the 5’ flanking region
CYP2E1*1Cx2	CYP2E1.1
CYP2E1*1D	CYP2E1.1	8 repeats in the 5’ flanking region		Increased activity after alcohol exposure and in obese subjects
CYP2E1*2	CYP2E1.2	1132G>A	R76H		Reduced
CYP2E1*3	CYP2E1.3	10023G>A	V389I		Normal
CYP2E1*4	CYP2E1.4	4768G>A	V179I		Normal
CYP2E1*5A	CYP2E1.1	−1293G>C; −1053C>T (c1>c2); 7632T>A
CYP2E1*5B	CYP2E1.1	−1293G>C; −1053C>T (c1>c2)
CYP2E1*6	CYP2E1.1	7632T>A
CYP2E1*7A	CYP2E1.1	−333T>A
CYP2E1*7B	CYP2E1.1	−71G>T; −eeeT>A
CYP2E1*7C	CYP2E1.1	−333T>A; −352A>G
Additional SNVs, where the haplotype has not yet been determined
		6431C>A
		9630T>G
		1031C>T; 1199G>A; 1316C>T; 4451C>G; 4486G>T; 4529C>T; 4696G>A; 4845T>C; 4904T>C; 5625G>A; 6317C>T; 9745C>T; 9987C>G; 11024C>G; 11276T>C; 11356A>C
		11112A>T	H457L