Molecular cloning of a full-length cDNA for human alcohol dehydrogenase

We have cloned a full-length cDNA coding for human alcohol dehydrogenase (ADH; alcohol:NAD⁺ oxidoreductase, EC 1.1.1.1) from a human liver cDNA library constructed in phage λgt11. The library was screened by using a rabbit antibody against human ADH as a first probe, by the modified method of Young and Davis. Mixed 14-mer synthetic oligonucleotides encoding Asp-Asp-His-Val-Val and Gln-Cys-Gly-Lys-Cys were used as a second probe. These amino acid sequences are considered to be common in all three subunits (α, β, and λ) controlled by the ADH₁, ADH₂, and ADH₃ loci. Ten λgt11 recombinants of 35 positive plaques obtained by antibody screening contained inserted cDNAs of 1.5-2.4 kilobase pairs and were found to exhibit positive signals by hybridization with synthetic probes. One of them, with an inserted cDNA of 1631 base pairs, contained a sequence that encodes 374 amino acid residues of the human β₁ subunit, a chain initiation codon, a chain termination codon, and additional 3' and 5' untranslated regions. A complete amino acid sequence of the human β₁ subunit was deduced from the cDNA.