November 9, 2015

Genetic Aspects of Labrador Retriever Myopathy

In this study 164 Labrador Retrievers were observed; however, since 58 were found in some way related, they were the focus group. The trait that the researchers were investigating was myopathy, a disease that affects the muscles. First, the researchers identified how the animals were related and created a pedigree. Then they mapped the trait they were looking at on the pedigree. Seven dogs were found to have both genetic and clinical signs of the disease. 41 dogs had genes for the disease but did not show clinical signs; they were considered abnormal as well. Each dog was put through a clinical test and a genetic test, then afterward they were mapped on the pedigree. The clinical test was a physical and neurological examination as well as a biopsy of muscle tissue and a Creatine Kinase test of the blood serum. The frequency of the allele was modeled using Hardy-Weinberg equilibrium.

Of the dogs in the study seven were clinically diagnosed. All other dogs had a clean bill of health and were in the pedigree in order to model how the gene was passed down from parent to offsring. All of the dogs had multiple tests performed on them in order to figure out what kind of tissues were present in sick dogs versus healthy dogs. Dogs in the healthy group were on average older than dogs in the sick group. The pedigree analysis showed the familial relationship, with multiple generations. One branch of the pedigree showed large amounts of inbreeding while other branches less so. ​

Bley, T., Cl Gaillard, Th Bilzer, K.g Braund, D. Faissler, F. Steffen, S. Cizinauskas, J. Neumann, T. Vögtli, R. Equey, and A. Jaggy. "Genetic Aspects of Labrador Retriever Myopathy." Research in Veterinary Science 73 (2002): 231-36. Print.

http://www.sciencedirect.com/science/article/pii/S0034528802000346