Identification and characterization of three large deletions and a deletion/polymorphism in the CFTR gene

Hum Mutat. 2005 May;25(5):504. doi: 10.1002/humu.9335.


Cystic fibrosis (CF) is mainly caused by small molecular lesions of the CFTR gene; mutation detection methods based on conventional PCR do not allow the identification of all CF alleles in a population and large deletions may account for a number of these unidentified molecular lesions. It is only recently that the availability of quantitative PCR methodologies made the search for large gene rearrangements easier in autosomal diseases. Using a combination of different methods, nine of the 37 unidentified CF alleles (24%) were found to harbor large deletions in our cohort of 1600 CF alleles. Three are new deletions, and we report the breakpoints of the previously described EX4_EX10del40kb deletion. An intronic deletion polymorphism affecting intron 17b was also found on almost 1% of "normal" chromosomes. Examination of the breakpoint sequences confirmed that intron 17b is indeed a hot spot for deletions, and that most of these rearrangements are caused by non-homologous recombination.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Base Sequence
  • Child
  • Cystic Fibrosis / genetics*
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics*
  • DNA Mutational Analysis
  • Female
  • Genetic Testing
  • Haplotypes
  • Humans
  • Infant
  • Male
  • Molecular Sequence Data
  • Polymorphism, Genetic*
  • Sequence Deletion*


  • CFTR protein, human
  • Cystic Fibrosis Transmembrane Conductance Regulator