GM2 Gangliosidosis (Discovered in the Japanese Chin)

First signs of GM2 gangliosidosis are usually observed at one year of age. Characteristic signs include ataxia (uncoordinated movements), intention tremors of the head, vision impairment, altered mental status, and feeding difficulties. GM2 gangliosidosis is a progressive condition, so affected dogs will have increasing difficultly with everyday tasks such as walking and going up stairs, and may need assistance. Affected dogs are usually euthanized on welfare grounds by two years of age.

Upon initial observation of clinical signs, affected dogs should be closely monitored to assess welfare, and devise a supportive care treatment plan. As clinically signs are progressive, affected dogs are usually euthanized on welfare grounds by 2 years of age.

There are many responsibilities to consider when breeding dogs. Regardless of test results it is important that your dog is in good general health and that you are in a position to care for the puppies if new responsible owners are not found. For first time or novice breeders, advice can be found at most kennel club websites.

This disease is autosomal recessive meaning that two copies of the mutation are needed for disease signs to occur. A carrier dog with one copy of the GM2 Gangliosidosis mutation can be safely bred with a clear dog with no copies of the GM2 Gangliosidosis mutation. About half of the puppies will have one copy (carriers) and half will have no copies of the GM2 Gangliosidosis mutation. Puppies in a litter which is expected to contain carriers should be tested prior to breeding. Carrier to carrier matings are not advised as the resulting litter may contain affected puppies. Please note: It is possible that disease signs similar to the ones caused by the GM2 Gangliosidosis mutation could develop due to a different genetic or clinical cause.