Background: The incidence of cystic fibrosis (CF) is low in the isolated Finnish population and the Finnish CF mutation spectrum has differed from many European countries.
Methods: We have analyzed the mutation spectrum and the geographical distribution of CF mutations in Finland covering the last 18 years (1987-2004).
Results: A total of 14 mutations were identified; two of them new, 774insT and S589T (G>C at 1,898). The overall coverage of mutations was 97% (99/102 chromosomes). The most frequent mutations were F508del and 394delTT, found in 36% (37/102) and 35% (36/102) of the CF chromosomes respectively. Of the rare mutations, a mutation of presumable Slavic origin, CFTRdele2.3 (21 kb), was enriched in a rural isolate with a frequency of 5,9% (6/102), and a mutation that possibly indicates Swedish influence, 3659delC, was scattered throughout the country with a similar frequency of 5,9% (6/102). G542X, R1162X, R117H, 3732delA, 1,898 + 3A >C, S1196X, S945L, W57R, 774insT and S589T were each identified in a number of chromosomes from one to three.
Conclusions: Our observations of the Finnish CF mutation spectrum fit well with the characteristics of Finland as a population of multiple local founder effects.