High frequency of cystinuria among jews of Libyan origin

Seven of 24 unrelated Israeli Jewish families affected with cystinuria were of Libyan origin. Five of these seven families were intensively investigated and heterozygotes were identified in four of them. This indicates that, contrary to other populations, in this community cystinuria is mainly of type II or III. Among randomly screened healthy school children of Libyan origin 3–4% were found to be heterozygotes for cystinuria. It is estimated that in this community the frequency of genetically determined cystine urolithiasis is about 1:2,500.