Dog days for ALS

A genome-wide association study has found that the mutation responsible for canine degenerative myelopathy (DM) is the same as that for human amyotrophic lateral sclerosis (ALS).

While the discovery will eventually lead to a diagnostic test for owners of several affected breeds, the researchers say it will also provide an excellent animal model by which to study ALS, also known as motor neurone disease (MND) and Lou Gehrig’s disease.

DM predominantly affects breeds such as German shepherds and corgis, but also Rhodesian ridgebacks, boxers and Chesapeake Bay retrievers. It mainly affects dogs over eight, is not sex specific and has similar demyelination and axon loss observed in ALS.

Researchers from the University of Missouri and the Broad Institute in Massachusetts used genome-wide association mapping on 38 DM-affected corgis and 17 controls and tracked the mutation to the region containing the SOD1 gene. This is the same gene affected in many cases of ALS.

While the human disease is most commonly studied in transgenic rodents, the researchers believe dogs will be a better model to study as the mutation is predominantly spontaneous and the disease progression and clinical spectrum are more similar to those experienced by humans.

The researchers also hope the finding will lead to better screening of the affected breeds. The study was published this week in the Proceedings of the National Academy of Sciences.