A new test for the diagnosis of Gaucher disease is described. The test is designed to screen large numbers of clinical specimens from high-risk populations. It consists of duplex PCR amplification of genomic DNA followed by hybridization to alkaline phosphatase-conjugated allele-specific oligonucleotide probes (ASOs). High melting temperature PCR primers were used to increase specificity and eliminate the need for a separate annealing step. All hybridization and washing steps were performed at one temperature. Chemiluminescent detection of signals is fast, and results are easily interpreted directly from x-ray films. Currently, the test is being used in our laboratories to screen Ashkenazi Jewish populations in whom Gaucher disease is common.