title: Cystic fibrosis transmembrane conductance regulator gene mutations and glutathione S-transferase null genotypes in cystic fibrosis patients in Brazil.
abstract: OBJECTIVE
  To determine the effects that mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene and deletion of the glutathione S-transferase (GST) genes mu-1 (GSTM1) and theta-1 (GSTT1) have on the clinical course of cystic fibrosis (CF) in patients residing in the southeastern region of Brazil.
  
  
  METHODS
  The study sample consisted of all consecutive CF patients treated at the Hospital de Clínicas School of Medical Sciences of the State University at Campinas between March of 2002 and March of 2005. We included 66 CF patients. Genomic DNA was analyzed by polymerase chain reaction and restriction endonuclease digestion for the identification of the genotypes.
  
  
  RESULTS
  The DF508 mutation of the CFTR gene was found in 44 patients (66.7%). The null genotypes GSTM1, GSTT1 and GSTM1/GSTT1 were found in 40.9%, 15.2%, and 3.0% of the patients, respectively. The DF508 CFTR mutation was more common in patients diagnosed with CF before 2.5 years of age than in those diagnosed later (75.5% vs. 41.2%; p = 0.008). The frequency of the DF508 CFTR mutation, as well as of the GSTM1 and GSTT1 genotypes, was not found to be associated with gender, ethnicity, pulmonary disease status, or pancreatic disease status.
  
  
  CONCLUSIONS
  When the patients were stratified by clinical and epidemiological features, the frequencies of the GSTM1 and GSTT1 null genotypes were similar, suggesting that the inherited absence of these enzymatic pathways does not alter the course of CF. However, the high frequency of the DF508 CFTR mutation found in younger children suggests that it influences the age at diagnosis of CF in this region of Brazil.
authors.affiliation: Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brasil. carmenl@fcm.unicamp.br
authors.forename: Carmen Silvia Passos
authors.initials: CS
authors.lastname: Lima
authors.forename: Manoela Marques
authors.initials: MM
authors.lastname: Ortega
authors.forename: Fernando Augusto Lima
authors.initials: FA
authors.lastname: Marson
authors.forename: Roberto
authors.initials: R
authors.lastname: Zulli
authors.forename: Antônio Fernando
authors.initials: AF
authors.lastname: Ribeiro
authors.forename: Carmen Silvia
authors.initials: CS
authors.lastname: Bertuzzo
mesh_terms: D001938:Brazil / Q000453:epidemiology; D016009:Chi-Square Distribution; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000235:genetics*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D009154:Mutation / Q000235:genetics*
chemical_list: D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D005982:Glutathione Transferase; C413545:glutathione S-transferase T1