Cerebellar Abiotrophy (CA)
Inheritance: Autosomal recessive
Symptoms: The main clinical symptom is ataxia with head tremours, poor co-ordination and a high step while walking.
Description:
Caused by degeneration of neurons in the cerebellar cortex. Two forms of the disease were identified in kelpies which correlate with similar symptoms in border collies from Australian working and ANKC lines.
These are two forms of the disease: An Early Onset Form (4-16 wo) which appears to be recessive with possible low penetrance and a Late Onset Form (4mo +) which appears to be recessive. Symptoms can range from mild with a noticable intention tremour with barely noticable incoodination and a high stepping gait, to sever which includes a pronounced intenion tremour, complete lack of coodination and occasional fitting. The late onset form has a poor prognosis and most pups are euthanased by 8-10 mo. Dogs with the early onset form can have mild symptoms and live a normal lifespan. Both forms are found in border collies.
Separate marker tests for the early onset and late onset forms were developed by Annie Pan at the University of Sydney building on the original work by Prof Alan Wilton at the University of New South Wales.
According to the early research by Shearman and Wilton all affected border collies (ANKC) they were studying could be traced back to small number of related common ancestors within eight generations. They postulate that due to the use of a popular sire in a small gene pool and inbreeding the disease manifested.
The earliest published reports of CA in border collies are NZ (1980) and Australia (2002).
A good summary of CA and the current status of the research can be found on the WKC web site.
The DNA test became available in late 2019.