[Genotype and genetic diagnosis of APRT deficiency]

Adenine phosphoribosyltransferase (APRT) deficiency is one of the most common genetic diseases among the Japanese and is transmitted in an autosomal recessive manner. Urolithiasis is a typical symptom of this disease. Molecular analysis of the deficient APRT alleles revealed that 96% of disease-causing genes among the Japanese was accounted for only three alleles. Therefore, genetic diagnosis can be performed on most of the patients without determining the mutant sequence in each family. The ASO-PCR hybridization method differentiated all of these alleles. Linkage analysis using neighboring RFLP markers revealed that each of the three mutant APRT alleles had a common ancestral origin.