report of slc3a1/rbat gene mutations in iranian cystinuria patients: a direct sequencing study

background: considering a few studies on the genetic basis of the cystinuria in the middle east and the population-specific distribution of mutations in the slc3a1 , we tried to find genetic variants in three exons (1, 3, and 8) of slc3a1 . materials and methods: in this study, exons 1, 3, and 8 of slc3a1 gene of 25 unrelated cystinuria patients searched for genetic variations by polymerase chain reaction and sequencing. results: there were five different variations in our studied population. we found one mutation in the slc3a1 gene including missense variant m467k and identified three polymorphisms: nonsynonymous variant g38g, c. 610 + 169c>t and c. 610 + 147c>g within the slc3a1 gene, and one new variant. conclusion: our results confirm that cystinuria is a heterogeneous disorder at the molecular level and more studies are needed to identify the distribution and frequency of mutations causing cystinuria in the iranian population.   key word: aminoaciduria, cystinuria, rbat, slc3a1 , transport