A family with atypical cystic fibrosis: brother and sister with heterozygosity for both G542X and R117H.
Clinical manifestations of cystic fibrosis (CF) are variable. Genetic and environmental factors that determine whether an individual will develop associated complications are still under investigation. The present study reports the genetic analysis of a family with different clinical forms of CF and addresses the difficulty of CF diagnosis in an individual with mutant alleles G542X and R117H because of the variable phenotype associated with R117H mutation. Both children in this family were heterozygous for G542X/R117H with the same thymine sequence (7T/9T) in intron 8 of CF transmembrane conductance regulator. The girl was diagnosed with CF, whereas the boy was diagnosed with azoospermia as the sole clinical manifestation. The possible implication of the hemochromatosis gene as a CF modifier locus was analyzed because the 2 children had the same genotype. No genetic differences were detected between brother and sister that explained the different clinical manifestations of CF.
Farez-Vidal
M Esther
ME
Servicio de Bioquímica, Hospital Universitario San Cecilio, Granada, Spain. efarez@ugr.es
Gómez-Llorente
M Amelia
MA
Gómez-Llorente
Carolina
C
Blanco
Sonia
S
Casas-Maldonado
Francisco
F
Campoy
Cristina
C
Gómez-Capilla
José Antonio
JA
D003550:Cystic Fibrosis / Q000235:genetics* / Q000503:physiopathology*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D004252:DNA Mutational Analysis; D019075:Electrophoresis, Capillary; D005190:Family; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D010375:Pedigree; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide
C505032:CFTR protein, human; D019005:Cystic Fibrosis Transmembrane Conductance Regulator