A NEW APPROACH FOR THE RAPID DETECTION OF COMMON AND ATYPICAL ALDEHYDE DEHYDROGENASE ALLELES

A strong protection against the development of alcoholism is exerted b y a point mutation in the gene coding for low K(m) aldehyde dehydrogen ase (ALDH), i. e. ALDH2. We report a non-radioactive method for determ ining the common and atypical human mitochondrial aldehyde dehydrogena se (ALDH2) genotypes. This method is based on the fact that the base c hange (G --> A) in Exon 12 of the ALDH, gene abolishes an Eco57 I rest riction site (CTGAAG --> CTAAAG). A GC-clamp attached- oligonucleotide was designed to yield a 176 base pair product by the polymerase chain reaction. After amplification, the resulting fragment containing the normal nucleotide sequence is cut by Eco57 I into two segments (131 ba se pairs + 45 base pairs) while the fragment containing the mutated se quence remains intact (176 base pairs). These are visualized by staini ng with ethidium bromide on agarose gels without blotting, hybridizati on or autoradiography.