delta F508 deletion in cystic fibrosis in Italian families.

In 20 Italian families with cystic fibrosis (CF), restriction fragment length polymorphisms were detected by five linked markers; a strong linkage disequilibrium is observed between the haplotype B (alleles 2/1 with respect to KM19/XV2c) and CF. The frequency of the delta F508 deletion in CF chromosomes of this sample is 50%. A significant correlation is found between the absence of the delta F508 mutation and pancreatic sufficiency.