Molecular characterization of WD deficiency in Cyprus

In the present study, we determined the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency in Cyprus using two different procedures in two separate adult population groups: a semiquantitative fluorescence test on blood spotted on filter paper and a quantitative spectrophotometric test on liquid blood. The frequency of G6PD deficiency among healthy adult males was found to be 5.1% using the semiquantitative procedure and 6.4% using the quantitative procedure. Neither method was able to detect all the expected female heterozygotes (5.3% and 47.1% of the expected number, respectively). A total of 21 mate hemizygotes, 1 female homozygote and 9 female heterozygotes that tested positive for G6PD deficiency were studied at the molecular level. All 32 chromosomes were genotyped and five different mutations were identified. The Mediterranean mutation in exon 6 (563C-->T) (Ser188Phe) was found to be the most common variant in the Cypriot population, accounting for 52.6% of the deficient alleles. In the remaining chromosomes, four different mutations were identified: three known mutations, Kaiping 1388G --> A (Arg463His), Chatham 1003G --> A (Ala335Thr) and Acrokorinthos 463C --> G (His155Asp), and one previously undescribed mutation in exon 3, 148C --> T (Pro50Ser), which we called G6PD Kambos. We conclude that the frequency of G6PD deficiency in Cypriot males is 6.4%, and that this deficiency is the result of several different mutations. Although all the individuals carrying the Mediterranean variant can be detected using a semiquantitative screening method, a quantitative enzyme measurement is required to detect the G6PD variants with less severe enzyme deficiencies, while the most appropriate method for heterozygote detection is DNA analysis. (C) 2004 Elsevier Inc. All rights reserved.