Neuropathy with splayed forelimbs (JNS)

Gene: UCHL1

Transmission: Autosomal recessive

For an autosomal recessive genetic disease an animal must have two copies of the mutation in question to be at risk of developing the disease. Both parents of an affected animal must be carriers of at least one copy of the mutation. Animals that have only one copy of the mutation are not at risk of developing the disease but are carrier animals that can pass the mutation on to future generations.

Mutation: Substitution, UCHL1 gene; c.979 G>A ; p.(E327K), chr.6.

Medical systems: Musculoskeletal, nervous

Breeds: Jersey

Age of onset of symptoms: From birth.

A recent congenital anomaly of splayed forelimbs was identified in Jersey calves in the United States and named Jersey neuropathy with splayed forelimbs (JNS).  The phenotype also included an inability to stand, craniofacial anomalies, and dislocated shoulders, as well as neurological symptoms including degenerative myelopathy, rigidity of neck and head muscles and convulsions.  Pedigree analysis of affected calves revealed a common ancestor.  Molecular studies identified a mutation within the UCHL1 gene on chromosome 6.  The UCHL1 gene codes for a protein enzyme that is highly expressed within neurons and is required for normal axon function.  The frequency of the mutation within the Jersey population in the United States was estimated to be 8.2%.  A DNA test will allow producers to identify carrier animals (M/N) to eliminate the disease and mutation from their animals via selective breeding.

References:

OMIA link: [2298-9913]

Al-Khudhair A, Null DJ, Cole JB, et al. (2022) Inheritance of a mutation causing neuropathy with splayed forelimbs in Jersey Cattle. J Dairy Sci. 105(2):1338-1345.  [pm/34955244]

Contributed by: Yasmine Caldas and Carolanne Garneau, Class of 2028, Faculty of Veterinary Medicine, University of Montreal.  (Translation, DWS)