Description of a symptomless cystic fibrosis L346P/M348K compound heterozygous Cypriot individual.
During the past few years we have been testing the hypothesis that Cyprus may have been spared many severe cystic fibrosis (CF) cases but not cystic fibrosis transmembrane conductance regulator (CFTR) mutations. We have been analysing by molecular methods patients with atypical mild phenotypes where CF enters the differential diagnosis. With this approach we identified a mutation, L346P, which in association with the severe mutation delta F508 or 1677delTA, confers a mild and atypical presentation. Recently, we identified another entirely symptomless 48-year-old individual, with genotype L346P/M348K. The fact that M348K was initially identified in a severely affected Italian patient strengthens the hypothesis that L346P, a putative mild mutation, is dominant over severe ones. One other explanation is that M348K is not a causative defect but a rare polymorphism. These findings have important implications for genetic counselling, especially when the counselling is sought by concerned couples for prenatal diagnostic purposes.
Deltas
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CC
Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.
Boteva
K
K
Georgiou
A
A
Papageorgiou
E
E
Georgiou
C
C
D002675:Child, Preschool; D003535:Cyprus; D003550:Cystic Fibrosis / Q000235:genetics*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D005260:Female; D006580:Genetic Carrier Screening; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length
C505032:CFTR protein, human; D019005:Cystic Fibrosis Transmembrane Conductance Regulator