Genetic Test for Congenital Idiopathic Megaesophagus in German Shepherd Dogs

CHF Grant 02709: Identification of Genetic Risk Factors Contributing to Gastrointestinal Motility Disorders

Publication:
Bell, S. M., Evans, J. M., Evans, K. M., Tsai, K. L., Noorai, R. E., Famula, T. R., Holle, D. M., & Clark, L. A. (2022). Congenital idiopathic megaesophagus in the German shepherd dog is a sex-differentiated trait and is associated with an intronic variable number tandem repeat in Melanin-Concentrating Hormone Receptor 2. PLOS Genetics, 18(3), e1010044. https://doi.org/10.1371/journal.pgen.1010044

What can we learn?
A genome-wide association study for canine idiopathic megaesophagus (CIM) in German Shepherd Dogs revealed an associated gene variant on canine chromosome 12. The gene in question plays a role in appetite, weight gain, and gastrointestinal motility. German Shepherd Dog males are affected by CIM almost twice as often as females. Investigators propose that estrogen plays a role in gastro-esophageal sphincter function as seen in humans.

Conclusion:
A genetic mutation has been identified that, along with sex, can predict a German Shepherd Dog’s risk of congenital idiopathic megaesophagus with 75% accuracy.