Page 15 - Chow LIfe - Summer 2020.pdf

implicated in slower drug processing in Greyhounds. Thanks to the collaborative efforts of the Chow Chow
Club, Inc. and CHF, researchers are now studying
A different enzyme that supports cytochrome P450 this unique Chow Chow mutation. They will examine
enzyme function, known as cytochrome P450 how this mutation affects cytochrome P450 enzyme
oxidoreductase or POR, was also found in varied function in Chows. They will also determine how
quantities in different dog breeds. In vitro testing prevalent the mutation is within the Chow Chow
(performed in a test tube or outside of a living breed and if it is present in other dog breeds.
being) confirmed that two variations in the POR-
coding gene found most commonly in Greyhounds These important studies may ultimately lead to
significantly reduced the efficiency of CYP2B11 genetic tests that veterinarians can use in the clinic
enzyme function. Evidence now showed that altered to choose the safest and most effective drugs for each
function in the CYP2B11 enzyme and one of its individual patient. Visit akcchf.org to learn how you
supporting enzymes could be responsible for adverse and your dog can participate in this study or provide
drug reactions in some dog breeds. a donation to help support research. Together, we will
ensure a healthier, happier future for all dogs.
The breakthrough came when investigators recently
identified a variation in the CYP2B11 gene in
Greyhounds that is responsible for its decreased
function in this breed and several other breeds. The
mutation causes abnormal mRNA molecules and
therefore decreased enzyme levels and slower drug
metabolism. Results, published in Scientific Reports,
reported that this mutation was also found in other
breeds including the Labrador Retriever and Golden
Retriever.
A unique Chow Chow mutation –

During these studies, the research team found a
different genetic mutation affecting the CYP2B11
enzyme in Chow Chows. The genetic variant also
appears to result in slower drug metabolism but
is not the exact same DNA sequence found in
Sighthounds and other breeds as described above.

Health Committee Report: Lew Klein

CCCI donated $18,500, through our What will be needed: hypersensitivity to sedative or anes-
AKC CHF Donor Advised Fund for thetic drugs that can be supported by
a grant to perform a study on genetic 1. DNA samples; two (2) cheek swab veterinary medical records.
mutation(s) in the Chow and sev- DNA brushes. (Instructions are in-
eral other closely related Northern cluded as well as a link to a video). Exclusion: Siblings (only one dog
breeds, that causes adverse reactions 2. A signed study consent form. from the same Dam/Sire pair); dogs
to anesthetic and sedative drugs, that have never been sedated or anes-
including butorphanol, aceproma- 3. A dog information sheet and thetized. The target enrollment is 300
zine, trazodone, hydromorphone, completed anesthesia history form, individual Chows, and 30 individuals
ketamine and midazolam. Dr. Court’s including owner name, address, for other breeds. Once these targets
Lab at Washington State University, email, phone number, dog call name, have been met, only dogs with a his-
that will be doing the study will be registered name, AKC number, age, tory of hypersensitivity to sedative or
mailing 100 DNA collection kits to sex, and history of sedative/anesthetic anesthetic drugs that can be support-
CCCI for voluntary DNA contribu- drug use and response to these drugs. ed by veterinary medical records will
tions at the upcoming CCCI National The participation criterion: AKC be considered for inclusion.
Specialty in September. I also hope to registered dog Chow or one of the For more information or to re-
get several CCCI volunteers that will other 6 included Northern breeds (Si- quest a DNA sample kit, contact
collect DNA samples at their local berian Husky, Tibetan Mastiff, Shiba me at lewis.klein555@gmail.com
regional specialties from Chows that Inu, Chinese Shar Pei, Akita, Alaskan
didn’t attend the National. Anesthesia Malamute); a history of being sedated (Note: A copy of the Consent &
and sedatives have been plaguing the or anesthetized. DNA samples from Anesthia History Form can be
Chow breed for many decades and we other breeds may be considered for found on pages 46-48)
finally have a chance to do something submission if there is a history of
about it. So please participate.