Charcot-Marie-Tooth neuropathy / CMT type 1J (ITPR3-related) - Lancashire Heeler

What does this test examine?

This genetic test analyses the ITPR3 c.5002C>T variant in the Lancashire Heeler. The condition is described as Charcot-Marie-Tooth neuropathy, CMT, CMT type 1J and ITPR3-related CMT with amelogenesis imperfecta. The disease therefore combines peripheral nerve disease with abnormal dental enamel formation.

What does this mean for the dog?

ITPR3 is involved in cellular calcium signalling, which is important for nerve function and tooth development. Dogs with two copies of the tested variant develop inherited neuropathy and can also show abnormal enamel. Reported features include muscle weakness, unstable gait, reduced reflexes, nerve conduction abnormalities, discoloured or poorly formed enamel and increased sensitivity to tooth wear.

Practical value of this test

• The result shows whether a Lancashire Heeler is clear, a carrier or genetically affected.
• Breeders can use carriers responsibly while avoiding matings that produce affected puppies.
• The test supports selection in a small breed where managing hidden carriers matters for population management.
• A clear genetic result helps with planning, follow-up and communication about puppies and breeding dogs.

Inheritance and result

This ITPR3-related CMT is inherited as an autosomal recessive trait. A dog with C/C does not carry the variant, C/T is a carrier and T/T causes the genetically affected genotype.