ASSOCIATION OF 1078 DEL-T CYSTIC-FIBROSIS MUTATION WITH SEVERE DISEASE

Apart from the high frequency of the Delta F508 mutation (81.81%) in B reton cystic fibrosis chromosomes, one mutation, 1078 del T, is also o bserved frequently (4.96%) in this group, in comparison with the rest of the French where it occurs with a frequency of 0.57%. These two mut ations account for more than 86.5% of the total CF mutations identifie d on Breton chromosomes. We have conducted an unblinded retrospective analysis of 25 patients with the 1078 del T mutation and compared thei r phenotypes with those of a group of 70 Delta F508 homozygous patient s. Both groups of patients had the same ethnic origin and were regular ly attending the same CF centre in Brittany, which makes this sample h ighly homogeneous despite the small size. The 1078 del T mutation appe ared to be associated with severe presentation of the disease with, ho wever, a trend to reduced mortality and less Pseudomonas aeruginosa co lonisation.