The Chihuahua dog: A new animal model for neuronal ceroid lipofuscinosis CLN7 disease?

This is a guest post by Kiterie Faller DVM DPhil MRCVS, a neurology and neurosurgery resident at the Small Animal Hospital of the University of Glasgow and a visiting fellow at TheGBLab.

In a collaboration between UCL and the University of Glasgow we have identified a mutation causing a lethal neurodegenerative disorder in Chihuahua dogs. This disease, called neuronal ceroid liposfuscinosis (NCL), affects young adult Chihuahua dogs (about one year old). They become progressively ataxic, blind and less responsive to their owners. This eventually leads to death before the age of two years old. The affected dogs carry a mutation in MFSD8 which is known to cause a form of NCL in young children (CLN7). In the latter, the initial clinical signs usually appear between 2 and 7 years, initially with seizures, visual loss and developmental regression. Unfortunately, the disease progresses to blindness, motor and mental impairment, and premature death before adulthood. There is no specific treatment for this devastating disorder.

We expect that these findings will help eradicate the disease in the Chihuahua breed. Moreover, thanks to the close proximity of the clinical signs and histological changes, this breed also represents an excellent animal model opportunity to better understand CLN7 and eventually test therapies for children. For more details on the work, see here.