Screening for cystic fibrosis gene mutations by multiplex DNA amplification

The utility of single-strand conformation polymorphism (SSCP) analysis: results obtained in families with Fabry's disease

Single-strand conformation polymorphism (SSCP) analysis is a widely used and relatively simple method for detection of sequence polymorphisms in DNA fragments. We have used this technique to screen the alpha-galactosidase gene, with the aim of identifying the disease causing mutations in families with Fabry's disease. Five single-base shift mutations were found, but a single base-pair deletion could not be recognized by SSCP. The risk of mistaking a neutral polymorphism for a mutation is illustrated, and the utility as well as the limitations of SSCP in screening and diagnostic use are discussed.

Screening for CF mutations in adult cystic fibrosis patients with a directed and optimized SSCP strategy

Twenty adolescent and adult cystic fibrosis (CF) patients have been studied for the presence of mutations in the CFTR gene. Mutations other than deltaF508 have been detected by comparison to the single-stranded conformation polymorphism (SSCP) pattern of known mutations in eight exons, in which 80% of the more common mutations are present. Each mutation was confirmed by direct sequencing. For each of the analyzed exons, optimal SSCP conditions have been determined that allow all available known mutations in that exon to be distinguished from each other. This approach allowed mutations to be defined in 75% of the non deltaF508 alleles and 92% of all CF alleles in this cohort.

Simultaneous detection of the two prevalent mutations in the cystic fibrosis gene in Reunion Island

A rapid method for the diagnosis of the most frequent cystic fibrosis mutations in the Reunion Island is described based on a coamplification polymerase chain reaction (PCR) followed by a single digestion using MseI. We have used this strategy to detect the two most frequent mutations in this area: delta F508 (in exon 10) and Y122X (in exon 4). These two mutations account for 70% of the CF chromosomes. This diagnosis method, which is rapid, easy, direct, and inexpensive, allows adult and neonatal carrier screening in this population.