CFTR Mutations in Chilean patients with cystic fibrosis

Abstract

Chilean population is a complex admixture of Amerindian, European and other ancestries. The estimated frequency of cystic fibrosis (CF) in the country is 1: 4,000, but it has been postulated that underdiagnosis is significant and may amount up to 50% of the cases. We have evaluated the presence and frequency of 11 of the most common CFTR mutations, according to the International CFTR Mutation Consortium, in 18 unrelated children with CF using an ARMS-based method. Mutations analyzed were deltaF508, deltaI507, G542X, G551D, G553X, R560T, R117H, W1282X, N1303K, 1717-1G->T and 621+1 G->T.

The type and frequency of mutations found were: delta F508, 17 % total alleles; W1282X, 19%; G551D, 3 %; G542X, 3%; undetected 58%. The other mutations were not observed. In five patients, no mutations were found. The low detection rate is similar to that described in other Hispanic populations, emphasizing that fact that there may be mutations unique to these ethnic groups. Addition of other common mutations to our panel, as well as identification of those specific to our population may increase the diagnostic yield and aid in studies to determine the carrier rate and incidence of the disease. (Funded by a grant from the Child Health Foundation, AL)