A UNIQUE MUTATION UNDERLYING CARBONIC-ANHYDRASE-II DEFICIENCY SYNDROME IN PATIENTS OF ARAB DESCENT

We have investigated, in the genomic DNA of ten Tunisian patients, the presence of a splice junction mutation at the 5' end of intron 2 in t he carbonic anhydrase II gene (CAII) previously described in six CAII- deficient patients presumed to be of Arab origin. All our patients wer e homozygous for this mutation and were mentally retarded, a character istic feature of the phenotype of patients with an Arabic background. This mutation is found exclusively in patients with an Arabic backgrou nd and thus may be confined to this ethnic group.