Characterization and rapid diagnostic analysis of DNA polymorphisms closely linked to the cystic fibrosis locus.

Six genetic polymorphisms, closely linked to the cystic fibrosis gene and useful in clinical linkage analysis, have been characterized and converted to a more rapid form of assay. Sequences flanking the metD (Ban I), metH (Msp I), XV-2c (Taq I), KM.19 (Pst I), MP6d-9 (Msp I), and J3.11 (Msp I) polymorphic restriction sites have been determined and used to design specific polymerase chain reaction (PCR) amplification primers and allele-specific oligonucleotide probes. All six of these polymorphisms were found to involve single-base alterations, and the XV-2c polymorphism was found to lie within an Alu repeat segment. These PCR-based tests, in conjunction with the CS.7 (Hha I) assay described elsewhere (Stanier P et al. Hum Genet 1988;80:309-10; Williams C et al. Lancet 1988;ii:102-3), provide a convenient, rapid, and reliable method of haplotype and linkage analysis, clinically useful in those situations where direct detection of mutations is not possible.