Screening Scheme Description

DNA test - Fuco.

Spaniel (English Springer)

Details about the disease

Fuco is characterised by deteriorating signs of the nervous system that progress over a period of several months, sometimes from an early age. The enzyme alpha-L-fucosidase is one of many required to break down complex compounds into simple molecules that the body can use. In affected dogs, those carrying two copies of the mutant gene, this enzyme is absent, the pathway is blocked and toxic compounds build up in the cells of the affected animal. The cells of the nervous system are particularly sensitive to these toxic intermediates. The disease is severe, progressive and ultimately fatal. It affects young adults, usually between 18 months and 4 years of age.

Clinical signs

Signs include incoordination and ataxia (loss of control of movement), change in temperament, loss of learned behaviour, loss of balance, apparent deafness, visual impairment and varying degrees of depression.

How it is inherited

The disease is described as an autosomal recessive condition. This means that a dog must inherit two copies of an abnormal gene (one from its mother and one from its father) before its health is affected. A dog that inherits only one copy of the abnormal gene (from its mother or its father) will have no signs of the disease, but will be a carrier and may pass the gene on to any offspring.

Which laboratories test for this condition?

A list of laboratories and DNA tests can be found at the following link

How to responsibly breed from your DNA tested dog

If, once your dog is DNA tested, you would like to find out what their DNA test results mean, or how to select the right mate to avoid producing affected puppies, then please read our breeding advice and information on the following link

How to find out if a potential mate has been DNA tested

The Kennel Club’s “Health Test Results Finder” allows you to find the results of DNA tests carried out as part of official Kennel Club DNA testing schemes for any dog on the Kennel Club’s breed register. To access this free health tool, please follow this link


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