Genomic screening for fucosidosis in English Springer Spaniels

Objective-To develop a robust molecular genetic test for alpha-L-fucosidosi s in English Springer Spaniels and to screen dogs from the United Kingdom a nd United States for the mutant allele. Animals-35 English-bred English Springer Spaniels, 60 American-bred English Springer Spaniels, and 1 affected dog and its parents from a family of Eng lish Springer Spaniels in Colorado. Procedure-Polymerase chain reaction analysis was used to amplify the mutate d region in the gene encoding alpha-L-fucosidase. High guanine-cytosine (GC ) content of the region required use of an amplification buffer with high p H. Mutant and normal alleles were separated by polyacrylamide gel electroph oresis. Molecular genetic lest results were compared with enzyme data. Results-A 262-bp PCR product was amplified from normal dogs and compared wi th a 248-bp product from affected dogs. Carriers had 1 copy of each allele, distinguishable by the 14-bp size difference. Two carriers among the Engli sh-bred dogs were identified by use of enzyme and genomic DNA analyses. The molecular defect in dogs from Colorado was proven to be the same as that i n British and Australian dogs. None of the other 60 American-bred dogs carr ied the mutant allele. Conclusions and Clinical Relevance-A PCR method that can be used to identif y dogs affected with or carriers of the autosomal recessive disease fucosid osis was established. Amplification was achieved within a GC-rich region, u sing a method that may be useful in overcoming amplification problems in GC -rich areas within other genes. Using this test, fucosidosis can be control led and ultimately eradicated from the English Springer Spaniel population.