These scientists are working to extend the lifespan of pet dogs—and their owners

Dogs can be used to study human aging. Sharing our environment is unique to them. Our pets live in our homes with us, breathing the same air we do, and sharing our exercise routines. Elaine Ostrander is the leader of a team that studies human and dog genetics at the National Human Genome Research Institute of the National Institutes of Health.

Many of the age related diseases that we do are also developed by them. Euthanasia is the leading cause of dog deaths. Most of the animals have cancer. Humans and dogs can both develop heart disease in later life. Dog brains aren't the same as human ones, but they do seem to develop a form of dementia Dogs don't tend to get diseases like humans do.

There are a lot of things in common. Aging of the immune system is one of the things that both dogs and people experience. He says it is very similar at the level of individual age-related diseases.

Aging in dogs is seven times quicker than in humans, and small dogs live longer than large ones. One year of dog life is equivalent to seven years of human life. In their first years of life, dogs seem to age faster than humans, and the pace slows as they get older.

Researchers are able to study the effects of potential anti-aging drugs over the entire lifespan, something that is much more difficult to do in people.

Dogs have an incredible variety. Extreme differences in size and appearance are only seen in dogs. A dog is 20 times more heavy than a dog. A dog resembles a bull terrier.

The variation makes the animals interesting. Most breeds have been around since the Victorian times. Modern dog breeding began in the late 19th century and owners bred their dogs for features such as a curly coat or a flat face. Dogs with certain features were selected by breeders.

The risks of certain diseases that vary between breeds are likely to be affected by the genetic differences between today's dog breeds.