Alcohol and alcoholism associated neurological disorders: Current updates in a global perspective and recent recommendations

Table 2 Summary of alcohol dehydrogenase and aldehyde dehydrogenase family gene

Enzyme	Gene name	Allelic variants	Amino acid differences between allele	Chromosomal location	Subunit components or protein name	Class
ADH	ADH1A			4q21-q23	α1α1	I
	ADH1B	ADH1B 1	Arg48, Arg370 (previously Arg47, Arg369)		β1β1	I
		ADH1B 2	His48, Arg370		β2β2
		ADH1B 3	Arg48, Cys370		β3β3
	ADH1C	ADH1C 1	Arg272, Ile350		γ1γ1	I
		ADH1C 2	Gln272, Val350		γ2γ2
	ADH4				π π	II
	ADH5				χ χ	III
	ADH6				μ μ	IV
	ADH7				σ σ	V
ALDH	ALDH1A1			9q21.13	Cytosolic aldehyde, dehydrogenase 1
	ALDH2	ALDH2 1		12q24.2	Mitochondrial aldehyde dehydrogenase

ADH: Alcohol dehydrogenase; ALDH: Aldehyde dehydrogenase.