MOLECULAR-GENETIC STUDY OF CYSTIC-FIBROSI S IN THE CHILEAN POPULATION- RELATIONSHIP ITS ITS CLINICAL EXPRESSION

Aiming to establish a genotype-phenotype relationship and to search a clinical expression in heterozygotes, 25 Chilean subjects with Cystic Fibrosis and 165 relatives were subjected to a clinical-molecular stud y. The most common mutations found worldwide were studied: Delta F-508 , G-542X, N-1303K, R-553X and G551D. Clinical and laboratory assessmen t comprised chest X-rays, spirometry, clinical evaluation, nutritional assessment, sweat test and carotenemia. Age at diagnosis was lower am ong homozygotes for the mutation Delta F-508. in this group, Brasfield and Schawchman scores were better, probably due to an earlier initiat ion of treatment. No other differences were found among genotypic grou ps or relatives. Genetic markers indicated a higher european component of the sample, compared to the general Chilean population.