Detection of Mutation in Exons 3 and 8 of SLC3A1 and Exons 4 and 10 of SLC7A9 Genes in Patients with Cystinuria in Iran

Abstract

Background: Cystinuria, one of the first diagnosed inborn errors of metabolism, recognized by hyperexcretion of cystine, lysine, ornithine and arginine into the urine. So far, two genes associated with cystinuria have been identified: SLC3A1 (2p16.3) that encodes the heavy subunit rBAT of the renal b0,+ transporter and SLC7A9 (19q13.1), which encodes the light subunit b0,+AT. Patients with type A cystinuria have two SLC3A1 mutations, whereas patients with type B have two SLC7A9 mutations and finally patients with type AB have one mutation in each gene. Considering the population-specific distribution of mutations in disease, limited studies on the genetic bases of the cystinuria have been done in Middle East. This research presents the results of mutation analysis on patients with cystinuria in Iran. Methods: Thirty unrelated patients with cystinuria operated to remove kidney stones were screened by urologist .The patients were analyzed for mutation using amplification refractory mutation system (ARMS) and polymerase chain reaction-Restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) methods. Findings: We found some variations including missense mutations, polymorphism and intron variant, but the most frequent mutations, M467T and also T216M and R333W, were not detected in our patients. Conclusion: Our research may confirm the ethnic distribution of mutations in cystinuria and this study can expand our concept of the genetic basis of cystinuria in Iranian patients.

Keywords

• Cystinuria
• Mutation
• Iran