Development of a snapback method of single-strand conformation polymorphism analysis for genotyping Golden Retrievers for the X-linked muscular dystrophy allele

Objective-To develop a snapback method of single-strand conformation polymo rphism (SSCP) analysis for genotyping Golden Retrievers for the X-linked mu scular dystrophy allele. Animals-20 Golden Retriever puppies from a colony with X-linked muscular dy strophy. Procedure-DNA spanning the canine dystrophin mutation was amplified by mean s of a polymerase chain reaction (PCR), using a primer modified to have an additional sequence at the 5' terminus. The primer was designed so that 1 t erminus of the single-stranded PCR product could anneal to the normal seque nce flanking the region of the mutation in the allele but not in the mutant allele. True disease status of the dogs was determined by means of a PCR a nd restriction digest protocol. Results-Snapback SSCP analysis allowed for accurate and unambiguous genotyp ing of unaffected, carrier, and affected dogs, whereas conventional SSCP an alysis, using the unmodified primer, did not. Creatine kinase activities me asured within 24 hours after birth were not consistent with genotype. Conclusion and Clinical Relevance-Snapback SSCP analysis provided a simple, fast, and accurate method for genotyping Golden Retrievers for the mutatio n known to cause X-linked muscular dystrophy.