A rapid method for detecting the predominant Ashkenazi Jewish mutation in the Bloom's Syndrome gene

Bloom's syndrome (BS) is a rare, autosomal recessive disease characterized by sun sensitivity, short stature, and predisposition to cancer. Although rare in the general population, BS is more common in the Ashkenazi Jewish population (German, 1993). The isolation of the gene for BS, known as BLM, has permitted the identification of mutations within the gene and the discovery that most BS individuals of Ashkenazi Jewish origin carry the identical 6-bp deletioin/7-bp insertion at position 2,281 of BLM (blm(Ash)). We have developed a rapid method for detecting blm(Ash) based on restriction enzyme digestion of a PCR product containing the mutation. blm(Ash) creates a restriction site within the amplified fragment allowing distinction of normal and mutant DNAs. This method has been designed for use with genomic DNA or cDNA.