Could Your Dog Help Cure Cancer? Researcher Wants to Know

[Guest guest]

Canine Cancer

Man's best friend may be able to give us more than unconditional

love. As this ScienCentral News video reports, mapping of the dog

genome could shed new light on the cause of different cancers.

Doggie DNA

Man may have more in common with his best friend than the love of

fresh air and a hearty meal. Dogs suffer from many of the same

diseases that people do, including many different forms of cancer.

" We see melanoma in these dogs, we see breast cancer, skin cancer, "

says Elaine Ostrander, professor of genome sciences and zoology at

the Fred Hutchinson Cancer Research Center. " Really most of the

things you're thinking about when you're thinking about your own

health are things that you should be thinking about your dog's health

as well. "

That's because the dog's genetic make-up is so similar to our

own. " The genome sequence of the dog and the genome sequence of

humans differs by less than one or two percent, " says Ostrander. " So

it's not surprising that the same genes are going to be responsible

for cancer in dogs as are responsible in humans. And we know about

one to three or one to four dogs will get cancer at some point in

their lifetime, which is really the same rate that we see in humans. "

But there's an important difference among dogs—breeding. There are

over 300 different breeds of dog, and the pedigree of a purebred dog

requires both of its parents to be of the same breed. This, and the

fact that some dogs are the result of thousands of years of

inbreeding, ensures that breeds are somewhat isolated genetically. By

collecting and studying the DNA of different dog breeds, Ostrander

and her team are finding out why certain dog breeds tend to get

certain kinds of cancers. " What we are starting to observe is as we

map a gene for a particular disease, even though it's fairly complex

in the human population, [is that] in any given dog breed, we are

seeing only one to two genes [that] are primarily responsible for

that disease, and not the eight or nine or ten when we look in the

much more complicated human population, " says Ostrander.

In a study published in the journal Human Molecular Genetics, the

scientists identified a single gene that causes an inherited form of

kidney cancer in German shepherd dogs by studying a closely related

group of dogs. " All of these dogs were integrated or cross related in

some way, " explains Ostrander. " So we knew that whatever the reason

was that these dogs were getting kidney cancer, it was probably due

to a mutation in a single gene. That was one of the primary findings

of the study—it was due to a mutation in a single gene. "

The same gene in humans may cause human kidney cancer, showing that

dog breeds could point out human disease genes. " The genes that we

are going to find in dogs are really going to be important for human

health and biology, " Ostrander says.

Ostrander is always looking for different DNA samples from different

breeds, so your dog could help with her research. One way the DNA is

collected is by rubbing a cheek swab very quickly on the inside of a

dog's cheek. " Then we put it in a particular preservative, " says

Ostrander, " and then we can actually extract a couple of micrograms

of DNA from that quick rubbing of the inside of the dog's cheek. It's

completely painless. "

The other way doggie DNA is collected is through blood samples. " If a

dog has a veterinary visit anyway, we ask the dog owners to contact

us and we'll send the veterinarian a tube with an anticoagulant in

it, " says Ostrander. " Then the veterinarian can draw a blood sample

and we could actually get a large amount of DNA from a blood sample.

But we're happy to work with the dog owners either way. Some dog

owners prefer to do just the cheek swab. And whatever they're most

comfortable with is fine. "

This research was funded by the American Cancer Society.