ADH1B

Alcohol dehydrogenase 1B is an is_associated_with::enzyme that in humans is encoded by the ADH1B is_associated_with::gene.

The protein encoded by this gene is a member of the is_associated_with::alcohol dehydrogenase family. Members of this enzyme family metabolize a wide variety of substrates, including ethanol, is_associated_with::retinol, other aliphatic alcohols, is_associated_with::hydroxysteroids, and is_associated_with::lipid peroxidation products. This encoded protein, consisting of several homo- and heterodimers of alpha, beta, and gamma subunits, exhibits high activity for is_associated_with::ethanol oxidation and plays a major role in ethanol catabolism. Three genes encoding alpha, beta and gamma subunits are tandemly organized in a genomic segment as a is_associated_with::gene cluster.

The human gene is located on is_associated_with::chromosome 4 in 4q22.

Previously ADH1B was called ADH2. There are more genes in the family of alcohol and is_associated_with::aldehyde dehydrogenase genes. These genes are now referred to as is_associated_with::ADH1A, is_associated_with::ADH1C, and is_associated_with::ADH4, is_associated_with::ADH5, is_associated_with::ADH6 and is_associated_with::ADH7.

Variants
A is_associated_with::single nucleotide polymorphism (SNP) in ADH1B is is_associated_with::rs1229984, that changes is_associated_with::arginine to is_associated_with::histidine at residue 47. The 'typical' variant of this has been referred to as ADH2(1) or ADH2*1 while the 'atypical' has been referred to as, e.g., ADH2(2), ADH2*2, ADH1B*47his, or ADH1B arg47-to-his. This SNP may be related to alcohol consumption with the atypical genotype having reduced risk of is_associated_with::alcoholism.

Another SNP is is_associated_with::Arg369Cys.

Role in pathology
A marked decrease of ADH1B is_associated_with::mRNA was detected in corneal is_associated_with::fibroblasts taken from persons suffering from is_associated_with::keratoconus.