Molecular Diagnosis

, Volume 5, Issue 3, pp 235–238 | Cite as

R117H and IVS8-5T Cystic Fibrosis Mutation Detection by Restriction Enzyme Digestion

Brief Communications


The number of thymines in a thymine repeat in intron 8 (IVS8) next to the exon 9 of the cystic fibrosis gene (CFTR) affects the efficiency of this site to act as a splice acceptor site and the subsequent inclusion or skipping of exon 9 into the CFTR protein. Another source of genetic variation, responsible for mild cystic fibrosis (CF) and/or congenital bilateral absence of the vas deferens, is the mutation R117H, located in exon 4 of CFTR. Both these genetic variants can be detected using restriction site—generating PCR amplification. The severity of the CF phenotype is partly dependent on the IVS8 background on which R117H occurs; thus, it is important to be able to test clinically for both these variants. A method using restriction digestion of PCR product is presented.


cystic fibrosis R117H IVS8-5T restriction digestion 


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Copyright information

© Churchill Livingstone® 2000

Authors and Affiliations

  1. 1.Clinical PathologyState University of New York Upstate Medical UniversitySyracuse

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