‍After Henry was rescued, he was observed to have rear limb shakiness; a blood test revealed elevated Creatine Kinase level. A muscle biopsy was performed and tissue sample sent to the University of California, San Diego School of Medicine for Biopsy Report and Dystrophy Panel Reports.

‍Biopsy Report:

‍Observation:

‍Unfixed and fixed biopsies were submitted from the triceps and vastus lateralis muscles. The unfixed biopsies were evaluated in frozen sections and the fixed biopsies evaluated in routine paraffin sections. A marked variability in myofiber size was present with fiber diameters ranging from 19-125 µm. Scattered atrophic fibers had a round shape and were of both fiber types. A type1 fiber predominance was present without obvious fiber type grouping. Intramuscular nerve branches were normal in appearance. Sporadic necrotic fibers undergoing phagocytosis and regenerating (type 2C) fibers were observed. Minimal mixed mononuclear cell infiltrations were present having an endomysial and perimysial distribution. No fibrosis, fiber loss, organisms or other specific cytoarchitectural abnormalities were observed.

‍Conclusion:

‍Degenerative, regenerative and mild inflammatory myopathy in both the triceps and vastus lateralis muscles consistent with a form of congenital myopathy. The pathological changes along with the young age of onset, markedly elevated CK activity, and another affected littermate support a congenital myopathy, possibly dystrophic in nature. To further investigate this myopathy, the Dystrophy Panel (Test 907.1) is suggested to test for the most common forms of muscular dystrophy in dogs. This additional testing can be performed on frozen muscle we have archived on Henry. Please advise if you wish to add this additional testing.

‍Dystrophy Panel Report:

‍Observation:

‍Cryosections from the vastus lateralis muscle and an archived control muscle were incubated with several polyclonal and monoclonal antibodies against dystrophy associated proteins including the rod and carboxy-terminus of dystrophin, , , and d-sarcoglycans, and a and -dystroglycan. Other antibodies used included those against utrophin, spectrin, laminin 2 (4F11), collagen VI (3G7), dysferlin (hamlet), caveolin 3 and developmental myosin heavy chain (dMHC). The staining intensity for the rod-domain of dystrophin was normal in appearance with patchy staining for the carboxy terminus of dystrophin. The staining intensity for , b, , d -sarcoglycans and a, -dystroglycan were all normal in appearance. Sporadic developmental myosin heavy chain (dMHC) positive regenerating fibers were present. Utrophin antibody staining not increased on the muscle sarcolemma. Antibody staining for laminin 2, caveolin3 and dysferlin were all normal in appearance. Increased collagen VI staining indicated endomysial fibrosis. Spectrin antibody staining was decreased suggesting partial tissue degradation.

‍Conclusion:

‍Partial dystrophin deficient muscular dystrophy is suggested by the staining pattern with the DYS2 antibody against the carboxy terminus of dystrophin. Staining for the other dystrophy associated proteins were similar to controls. Gene sequencing would be necessary to confirm a specific mutation. No specific treatments are currently available for any of the muscular dystrophies.

‍At their reunion Henry and Harry (pictured above as puppies) acted as though no time at had passed. When Harry dug the hole, Henry dropped in the stuffy toy! It was apparent that Harry enjoys better health than Henry. Harry’s exercise fatigue results in rest time, which is less severe than Henry’s “flopdowns.”

‍It has been mentioned that Harry tested negative for Myasthenia Gravis. Recently, his Wisdom Panel DNA results arrived! Harry is:

‍Australian Shepherd 29.0% (Henry Embark DNA 34.2%)

‍German 29.0%  (Henry Embark DNA 30.9%)

‍Anatolian 6.0%  (Henry Embark DNA 11.4%)

‍Great Pyrenees 17.0 %  (Henry Embark DNA 14.0%)

‍Border Collie 7.0 %  (Henry Embark DNA 9.5%)

‍Wisdom Panel DNA results show Harry’s Heterozygosity to be 30%; EmbarkDNA results show Henry’s “Coefficient of Inbreeding” to be 25%. It should be noted that data are analyzed, calculated, and represented differently by each DNA company.

‍MDR1 Multidrug Resistance 1: Normal MDR1 genes help move drugs and toxins out of the dog’s body and keeps many of them out of the brain. Dogs with MDR1 mutation can experience build up of toxic drugs, particularly in the brain. There are many common medications that aren’t tolerated by an MDR1 dog and the mutation is inherited — passed from parents to puppies.

‍DCM Dilated Cardiomyopathy: Harry’s Wisdom Panel DNA test reveals a single DCM mutation on one of two chromosome RBM20. Harry may never develop DCM, but could pass the mutation to about half his offspring if bred. Luckily, Harry (and Henry) are neutered!

‍Click here to read Henry’s Embark DNA blog post.