Lysosomal Storage Disease

Lysosomal Storage Diseases refer to a group of rare inherited metabolic disorders that result from defects in the function of lysosomes. Lysosomes are the “recycling centre” in cells and are supposed to process unwanted or worn-out material in a cell into a substance that the cell can use. The lysosomes use enzymes to do this processing, and if the enzyme exists in only small amounts or is absent altogether the recycling process doesn’t work, and the unprocessed material builds up, or is stored, in the cell. Eventually the stored material builds up so much that the cell cannot function any longer. When this happens in enough cells, disease symptoms appear.
The symptoms of Lysosomal Storage Diseases vary, depending on what type of cell is malfunctioning and what material is being stored. Some have a relatively early age of onset, others may not appear until middle or old age, and symptoms range from fairly mild, to severe and deadly. Storage disease symptoms can include developmental delay, movement disorders, seizures, dementia, deafness, and blindness.
Lysosomal Storage Disease is a genetically inherited disorder with an autosomal recessive mode of inheritance. This means that for a puppy to inherit the condition he must receive a positive gene from both parents. A genetic test is available to determine the status of the dog before breeding. The situation of a dog having “Hereditary Clear” status (i.e. neither of its parents carry the defective gene so he cannot carry it) exists. From January 2022 the Kennel Club will limit this status to two generations, testing individuals will then have to be undertaken.
The LRCGB tests all breeding stock and it is mandatory that breeders ensure at least one parent is normal (i.e. is not affected or carrying the LSD gene). This will ensure that no affected puppies are produced.

The diagram shows how carrier and non-carrier genes are passed to offspring, in our case, puppies. It is important to remember, however, that despite the implied average inheritance, each puppy will be the product of its own individual roll of the genetic dice and therefore the percentage values are not absolute.

Autosomal Recessive Inheritance
If you wish to have your dog tested for LSD, please contact the Chair of the Club’s Health Sub-Committee.