Analysis of APRT Mutations by Reverse-Transcription PCR

Abstract

Adenine phosphoribosyltransferase (APRT) is an enzyme of purine metabolism and its deficiency can lead to 2,8-dihydroxyadenine urolithiasis (1). The APRT gene is small (genomic region 2.6 kb, coding region 0.54 kb), contains five exons, and is located at 16q24. By sequence analysis of PCR-amplified genomic DNA, we have identified 18 different mutations in patients with APRT deficiency (2). Nine of these mutations, including two nonsense mutations, are located in exon 3. Several of the APRT mutations, including the TGG-to-TGA nonsense mutation at trp₉₈ in both alleles from patient ASA1 (3), have now been analyzed by reverse-transcription (RT-PCR). The results are presented here. RNA from the second patient with a nonsense mutation in both alleles in exon 3 (CGA-to-TGA, arg₈₇) (4) was not available for analysis.