- Paper Report
- Open Access
Genetic screening in cystic fibrosis
- James F Chmiel1
© Biomed Central Ltd 2001
- Received: 9 March 2001
- Accepted: 18 September 2001
- Published: 18 September 2001
- CFTR, cystic fibrosis, genetic testing, genotype analysis, mutational analysis
Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the CF transmembrane regulator (CFTR). To date, more than 800 mutations in CFTR have been described. The most commonly available commercial assay identifies less than 100 of the known CFTR mutations. When a CF patient undergoes genotype analysis, occasionally one or both of their mutations remain unidentified. As allele-specific therapeutics are developed, identification of both of an individual's mutations will increase in importance. The currently accepted standard for comprehensive screening of CFTR mutations is the labor-intensive denaturing gradient gel electrophoresis. The authors propose using a modified version of single strand conformation polymorphism and heteroduplex analysis (SSCP/HA) to identify mutations undetected by the commercial assay. The aims of this study are to verify the SSCP/HA detects known mutations not identified by commercial screening.
SSCP/HA was tested on the 20 CF alleles from 10 patients with typical CF, four of which alleles had been identified by commercial screening, and the 14 alleles from 7 patients with at least one symptom of CF but normal or borderline sweat chloride concentrations (so-called 'atypical CF'), one of which was identified by commercial screening were also identified by SSCP/HA. 11 of 16 CF alleles (69%) not identified by commercial screens were identified by SSCP/HA. Of 13 alleles from the 'atypical CF patients' not identified by commercial screen, three were found, by SSCP/HA, to be CFTR mutants. Extrapolation to the rest of the Center population indicates that commercial screening plus SSCP/HA would detect 95 % of CF alleles, similar to the more expensive and time consuming denaturing gradient get electrophoresis.
Single strand conformation polymorphism and heteroduplex analysis, PCR