A three base pair deletion results in the deletion of phenylalanine codon 508 (p.F508del). An HPRT minigene was also inserted into intron 11 in reverse transcriptional orientation relative to the gene. A mutant transcript is expressed and is identified in salivary glands, lungs, pancreas, kidney and small intestine at approximately 15% of the wild-type level, except in the salivary glands at 3%. The deletion mimics the deltaF508 mutation found in human cystic fibrosis patients. (J:27734)