Objective This study was conducted to determine the prevalence of alkaptonuria in the UAE population and to identify the genotype of affected individuals.
Subjects and Methods Urine samples were collected from 2981 pupils from government schools in Al Ain city and private schools in the city of Dubai selected in a three-stage sampling technique. Urine samples were analysed for homogentisic acid (HGA) by gas chromatography–mass spectrometry.
Results Urine from one child was highly positive for HGA, excreting a large amount of HGA. There were no symptoms of joint pain or other symptoms in any member of this family. The entire coding exons and splice sites of the HGD (HGO) gene was sequenced in the affected child, revealing a homozygous single nucleotide deletion at c342 delA in exon 3 leading to a frameshift at amino acid position 58 (R58fs). In this child’s family of 12 members a brother and a sister were also found to be homozygous for the same mutation. The mutation found in this Arab family has been reported in several populations including Turkish, Finnish, Slovak and Indian patients and was identical to the Turkish patients, strengthening the hypothesis that the R58fs mutation is an old mutation spread in a vast geographical area by human migration.
Conclusion Alkaptonuria may be more common than is thought, with a prevalence of one in 3000 in our population. In addition, our findings are likely to be helpful in the diagnosis of alkaptonuria in Arab and other middle eastern populations.