Neuronal Ceroid Lipofuscinosis 10 / NCL10 (CTSD-related) - American Bulldog

What does this test examine?

This genetic test analyses the CTSD c.597G>A variant in the American Bulldog. The condition is known as neuronal ceroid lipofuscinosis 10, NCL10, CLN10, cathepsin-D-related NCL and CTSD-related lysosomal storage disease.

CTSD encodes a lysosomal protein that is important for normal cellular breakdown processes. The tested variant disrupts this function and, with two copies, causes accumulation of autofluorescent storage material in nervous tissue.

What does this condition mean?

NCL10 in the American Bulldog is a progressive neurological disorder that usually becomes visible between one and three years of age. Affected dogs can develop mental dullness, ataxia, hypermetria, weakness, abnormal gait, tremors, seizures and behaviour change.

NCL disorders are lysosomal storage diseases in which nerve cells are gradually damaged. As a result, problems with vision, behaviour, coordination, movement and neurological function can increase over time.

Inheritance and result

The trait is inherited as autosomal recessive. Two copies of the variant cause the condition. Carriers have one copy, usually appear healthy, and can pass the variant on.

What does the result mean?

• Clear (GG): the tested variant was not detected.
• Carrier (GA): the dog carries one copy and can pass the variant on.
• Affected (AA): two copies cause CTSD-related NCL10 in the American Bulldog.

Practical value of this test

• Shows whether the dog is clear, carrier or genetically affected for the tested CTSD variant.
• Helps breeders avoid carrier-to-carrier matings and prevent puppies with a severe progressive neurological disorder.
• Provides valuable information before young, clinically normal or imported dogs are used for breeding.
• Supports line management when ataxia, behaviour change, vision loss, seizures or NCL occur in related animals.
• Makes communication with puppy buyers and fellow breeders more concrete because variant status is objectively known.

For breeders, this is especially useful because carriers can look healthy while two carriers together can produce affected puppies.