Test Detail

Congenital myopathy characterized by the presence of rod-shaped structures (nemaline rods) inside the muscle fibres, derived from sarcomere proteins. It affects the American Bulldog with weakness, arched posture and progressive muscle atrophy from an early age, with involvement of the respiratory and oesophageal musculature that conditions the prognosis. It is a natural model of human nemaline myopathies.

American Bulldog is the best-characterized breed. The carrier frequency in the breeding population is not systematically published (limited data).

- Genotype breeding dogs before mating\n- Do not mate two carriers: 25% risk of affected homozygotes\n- A carrier can be mated to a clear dog; offspring intended for breeding must be tested\n- Exclude affected homozygous animals from breeding\n- After a confirmed clinical case, do not repeat the parental mating and communicate the status to the buyer

Differential diagnosis with myotubular myopathy (XL-MTM) and other congenital myopathies of the puppy. Muscle biopsy shows nemaline structures (rods) in the fibre; immunohistochemistry with α-actinin highlights them. Involvement of the oesophagus and respiratory muscles conditions the prognosis.

1. Evans JM et al. 2016. Exome sequencing reveals a nebulin nonsense mutation in a dog model of nemaline myopathy. Mamm Genome 27:495-502. PMID: 27215641
2. OMIA:002137-9615 - Nemaline myopathy, NEB-related. https://omia.org/OMIA002137/9615/