Neuronal Ceroid Lipofuscinosis 4A / cerebellar ataxia (ARSG-related) - American Staffordshire Terrier

What does this test examine?

This genetic test analyses the ARSG c.296G>A variant in the American Staffordshire Terrier. The condition is known as neuronal ceroid lipofuscinosis 4A, NCL4A, cerebellar cortical abiotrophy, cerebellar cortical degeneration, cerebellar ataxia and ARSG-related lysosomal storage disease.

ARSG encodes arylsulfatase G, a lysosomal enzyme involved in cellular degradation pathways. The c.296G>A variant alters the enzyme and leads to accumulation of storage material in nervous tissue.

What does this condition mean?

This condition is slowly progressive and often becomes apparent in adulthood. Early signs can be subtle, but neurological decline gradually increases.

Affected dogs can develop behaviour changes, cognitive decline, ataxia, loss of coordination, seizures, motor degeneration and eventually premature death. Retinal function can also be affected.

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 (G/G): the tested variant was not detected.
• Carrier (G/A): the dog carries one copy and can pass the variant on.
• Affected (A/A): two copies cause the ARSG-related lysosomal storage disease/NCL4A.

Practical value of this test

• Shows whether a American Staffordshire Terrier is clear, carrier or genetically affected for the tested ARSG variant.
• Helps breeders avoid carrier-to-carrier matings and prevent puppies with a severe progressive neurological disorder.
• Provides valuable information before young or clinically normal dogs are used for breeding.
• Supports line management when ataxia, behaviour changes, vision loss 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 test is especially practical because carriers can look healthy while two carriers together can produce affected offspring.