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Updated: Jul 6, 2026

Plant Sample Preparation for Nucleoside/Nucleotide Content Measurement with An HPLC-MS/MS
Published on: February 24, 2021
[Adenine phosphoribosyltransferase deficiency and its purine metabolism]
1Institute of Rheumatology, Tokyo Women' s Medical University.
Abstract:
Adenine phosphoribosyltransferase (APRT) deficiency is a genetic disorder that causes 2,8-dihydroxyadenine (DHA) urolithiasis. Based on the level of residual enzyme activity in cell extracts, two types of APRT deficiency have been identified. Type I is complete enzyme deficiency. Type II shows residual activity in cell lysates, but enzyme activity is not demonstrable in intact cells. Patients with type II have at least one M136T allele and have been identified mainly in Japanese. Thus, in Japanese, patients with type I deficiency are homozygous for APRT*Q0 (null alleles) and patients with type II deficiency are either homozygotes with APRT*J (M136T allele) or compound heterozygotes with APRT*J/APRT*Q0.
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