UCLA researcher finds biological clock that reveals tissue age

By Casey Frye, CCNN Writer

old age
If aging could be slowed down, would this man have a naturally dark brown beard instead of white?

Unless you’re the seemingly immortal Gabrielle Williams, there’s no way to escape aging, and scientists don’t even know exactly why! However, a researcher from the University of California, Los Angeles (UCLA) has uncovered a special clock in the body that reveals why we age and a possible way to slow it down.

Now, this wasn’t one of those fancy time-tellers with an hour hand and a minute hand. Instead, the biological “clock” was based on certain chemicals that affect our DNA – you know, the master molecules that tell our bodies how to grow. Even though every one of our cells has exactly the same DNA, certain cells have only specific pieces of it activated. These small segments of DNA – called genes – are responsible for making cells function a certain way. The process involved in activating these genes, called “methylation,” is what the UCLA researcher used as a biological clock.

When the scientist compared methylation age to a person’s actual age, they found the biological clock was almost always the same. “Methylation levels either increase with age or they decrease with age,” said Steve Horvath, a professor of human genetics at the David Geffen School of Medicine at UCLA. “I identified 353 of these markers that are located on our DNA. I managed to aggregate their information so they arrive at a very accurate clock.”

However, while most cells matched the age of the person, others were very different. For example, the heart appears to be many times younger than the rest of the body by almost 10 years! Not too bad, eh? Well it is too bad that some body parts were a bit older. One of the major differences were found in a woman’s breasts. “Healthy breast tissue is about two to three years older than the rest of a woman’s body,” said Horvath. “If a woman has breast cancer, the healthy tissue next to the tumor is an average of 12 years older than the rest of her body.”

Horvath hopes this clock will come in handy for fighting aging related illnesses such as heart disease and cancer. Who knows, maybe it will eventually be used to fight old age itself and we can all become immortal.

Image of aging man courtesy of Randen Pederson on Flickr.