DNA Test for Fucosidosis in English Springer Spaniels
Fucosidosis is a lysosomal storage disease characterised by symptoms involving the central nervous system including impairment of mental and motor functions.
The genetic defect underlying fucosidosis in English Springer Spaniels has been identified by research groups in the UK and Australia. It is a deletion (ie a small segment of DNA is missing) within the gene α-L-fucosidase. On the basis of this information, we have developed a diagnostic test which will distinguish between normal, carrier and affected dogs. The test works by using the polymerase chain reaction to amplify the region of the gene that spans the deletion and then separating the DNA fragments on the basis of their size. The DNA fragment from the disease gene can be clearly recognised, being smaller than that from the normal form of the gene. Breeders will be sent results identifying their dog as belonging to one of three categories:
CLEAR: The dog has 2 copies of the normal gene and will neither develop fucosidosis, nor pass a fucosidosis gene to its offspring.
CARRIER: The dog has one copy of the normal gene and one copy of the mutant gene that causes fucosidosis. It will not develop fucosidosis but will, if bred from, pass on the mutant gene to,on average, 50% of its offspring.
AFFECTED: The dog has 2 copies of the mutant gene that causes fucosidosis and will develop the disease.
Fucosidosis is an autosomal recessive disorder. Crossing the three genotypes - clear, carrier or affected - will produce the following litters:
|clear x clear||all clear|
|clear x carrier||approximately 50% clear 50% carriers|
|clear x affected||all carriers|
|carrier x carrier||approximately 25% clear, 50% carriers 25% affected|
|carrier x affected||approximately 50% clear 50% affecteds|
|affected x affected||all affecteds|
Tests can be ordered through our Webshop http://www.ahtdnatesting.co.uk.