Missense mutations in the cystic fibrosis gene in adult patients with asthma

Asthma is a complex genetic disorder that affects 5% of adults and 10% of c hildren worldwide. The complete characterization of the cystic fibrosis tra nsmembrane conductance regulator (CFTR) gene identified missense mutations in 15% of 144 unrelated adult patients with asthma, but in none of 41 subje cts from the general population. The four more common mutations were analyz ed in an extended sample consisting of 184 individuals from the general pop ulation and did not show a significant difference in frequency. The hyperfu nctional CFTR M470 allele was detected in 90% of patients with CFTR missens e mutations, but in 63% of subjects from the general population and 63% of asthma patients without CFTR mutations. None of the patients with missense mutations had the 5T allele of intron 8 of CFTR, responsible for low CFTR l evels, while it was detected in 8% of asthma patients without CFTR mutation s and in 9% of subjects from the general population. These findings suggest a putative role for a combination of CFTR missense mutations, including th e M470 allele, in the genetic variability of asthma. Hum Mutat 14:510-519, 1999. (C) 1999 Wiley-Liss, Inc.