Phenotype/genotype correlation and cystic fibrosis related diabetes mellitus (Italian multicenter study)

Background: A genotype/phenotype correlation between early onset cystic fib rosis related diabetes (CFRD) and the N1303K mutation of the CF gene was pr eviously identified in a small series of 28 CFRD patients, out of 313 CF pa tients, Patients and methods: In order to confirm the observation, data of 141 CFRD patients out of 1,229 CF patients attending 14 Italian CF centers were col lected, All patients were older than 10 years and had been genotyped, Results: Delta F508 was the most frequent mutation (147/282 alleles: 52%) a nd N1303K the second most frequent mutation (18/282 alleles: 6.3%) in CFRD patients, without significant difference as compared with CF patients witho ut DM (52% vs 48.6% and 6.3% vs 5.1%, respectively). W1282X was the third m ost frequent mutation in CFRD patients, more frequent than in CF patients w ithout DM (5.3% vs 2%; p<0.001), Conclusions: Unlike the previous study, we did not find a higher frequency of the N1303K mutation in CFRD patients; moreover, data from this large CF series showed a significant correlation between the W1282X mutation and CFR D.