Spinocerebellar Ataxia (SCA) is an inherited neurologic disease with symptoms generally appearing between two to six months of age. Initial symptoms can include loss of balance and difficulties with coordination when walking or running. These symptoms are progressive and problems with movement coordination typically worsen with disease progression. Additional symptoms can include episodes of involuntary muscle twitching known as myokomia which can also progress and worsen with age resulting in over-heating. Affected dogs may even experience true epileptic seizures. The typical prognosis for SCA is not good and dogs suffering from the disease are typically recommended for euthanasia due to a poor quality of life.

• Basenji
• Chihuahua
• Jack Russell Terrier
• Parson Russell Terrier
• Russell Terrier
• Smooth Fox Terrier
• Tenterfield Terrier
• Toy Fox Terrier

A (CLEAR/NORMAL): These dogs have two copies of the normal gene and will neither develop spinocerebellar ataxia nor pass this mutation to their offspring.

B (CARRIER/NOT AFFECTED): These dogs have one copy of the normal gene and one copy of the mutation associated with this disease. They will not develop spinocerebellar ataxia but will, if bred, pass the mutation to 50% of its offspring, on average.

C (AT RISK/AFFECTED): These dogs have two copies of the mutation associated with this disease and are susceptible to developing spinocerebellar ataxia.