Molecular characterization of G6PD 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 male 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.
Drousiotou
Anthi
A
Department of Biochemical Genetics, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus. anthidr@cing.ac.cy
Touma
Elias H
EH
Andreou
Nicoletta
N
Loiselet
Jacques
J
Angastiniotis
Michalis
M
Verrelli
Brian C
BC
Tishkoff
Sarah A
SA
D019411:Clinical Laboratory Techniques / Q000592:standards; D003535:Cyprus / Q000453:epidemiology; D004252:DNA Mutational Analysis; D005260:Female; D005838:Genotype; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000175:diagnosis* / Q000453:epidemiology* / Q000235:genetics; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D017720:Molecular Epidemiology; D020125:Mutation, Missense; D015995:Prevalence; D013057:Spectrum Analysis