ScienceVideoSmarter IdeasDNA methylation

Biological Clock Hidden In Our DNA Can Identify Ages Of Specific Tissues, Scientist Says

Scientist Finds Real 'Biological Clock' Hidden In Our DNA
By 

Law student & former journalist

|

The age on your driver's license may not be exactly correct -- well, for certain parts of your body anyway.

A new study, published Monday in peer-reviewed journal Genome Biology, suggests that we all have an internal biological clock that tracks the aging process -- and may reveal the true age of our cells and tissues. It's hidden right in our DNA.

"The epigenetic clock really allows someone to objectively measure the age of cells and tissues," study author Dr. Steve Horvath, a professor of human genetics and biostatistics at the University of California, Los Angeles, told The Huffington Post. "Therefore, it can be used to study aging."

This internal "timepiece" may also be used to compare the various ages of elements in the body. For instance, in his research, Horvath found that female breast tissue ages several years faster than the rest of the body, which may explain why breast cancer is the most common cancer in women. Cancer also greatly accelerates the age of affected tissues.

(Story continues below.)

The original version of the Vitruvian Man by Leonardo da Vinci visualizes the ideal physical proportions of man. The epigenetic clock allows us to move beyond measuring physical proportions and to add a dimension of time: We are now able to quantify the age of most human tissues, organs and cell types. (Image and caption courtesy of Steve Horvath)

Horvath came across this biological clock after spending several years searching for an internal predictor of aging. He turned to DNA methylation, which is the biochemical process by which certain molecules that make up DNA are altered. Specifically, Horvath charted the effect that age has on this process -- from pre-birth to 101 years -- using nearly 8,000 samples of 51 types of tissue and cells taken from throughout the body.

From there, Horvath and his team were able to identify 353 markers within human DNA linked to methylation. They change with age and are present throughout the body. When evaluated together as a graded average, these markers provide a highly precise estimate of age. Eureka!

This allowed Horvath to develop an algorithm to determine the age of a certain sample, which he has opted to share publicly on the Internet. (UCLA has also filed a provisional patent on the research.)

While practical applications could include a test for cancer -- since malignant cells tend to age faster -- Horvath is more focused on how this biological clock relates to aging.

"Hopefully it can be used to study what causes aging and age-related disorders," he told HuffPost, adding that researchers could then focus on therapeutic intervention. Horvath likened potential procedures to resetting a clock.

But first, Horvath and his team must determine whether the biological clock relates to the process that causes aging. Only then could the clock be potentially reset.

Before You Go

Bizarre Genetic Engineering
Pollution-fighting plants(01 of05)
Open Image Modal
Scientists at the University of Washington are engineering poplar trees that can clean up contamination sites by absorbing groundwater pollutants through their roots. The plants then break the pollutants down into harmless byproducts that are incorporated into their roots, stems and leaves or released into the air. In laboratory tests, the transgenic plants are able to remove as much as 91 percent of trichloroethylene — the most common groundwater contaminant at U.S. Superfund sites — out of a liquid solution. Regular poplar plants removed just 3 percent of the contaminant. (credit:University of Washington)
Venomous cabbage(02 of05)
Open Image Modal
Scientists have recently taken the gene that programs poison in scorpion tails and combined it with cabbage. Why would they want to create venomous cabbage? To limit pesticide use while still preventing caterpillars from damaging cabbage crops. These genetically modified cabbages produce scorpion poison that kills caterpillars when they bite leaves — but the toxin is modified so it isn’t harmful to humans. (credit:File/Flickr:net_efekt)
Web-spinning goats(03 of05)
Open Image Modal
Strong, flexible spider silk is one of the most valuable materials in nature, and it could be used to make an array of products — from artificial ligaments to parachute cords — if we could just produce it on a commercial scale. In 2000, Nexia Biotechnologies announced it had the answer: a goat that produced spiders’ web protein in its milk. Researchers inserted a spiders’ dragline silk gene into the goats’ DNA in such a way that the goats would make the silk protein only in their milk. This “silk milk” could then be used to manufacture a web-like material called Biosteel. (credit:File/Flickr:maessive)
Flavr Savr tomato(04 of05)
Open Image Modal
The Flavr Savr tomato was the first commercially grown genetically engineered food to be granted a license for human consumption. By adding an antisense gene, the California-based company Calgene hoped to slow the ripening process of the tomato to prevent softening and rotting, while allowing the tomato to retain its natural flavor and color. The FDA approved the Flavr Savr in 1994; however, the tomatoes were so delicate that they were difficult to transport, and they were off the market by 1997. On top of production and shipping problems, the tomatoes were also reported to have a very bland taste: “The Flavr Savr tomatoes didn’t taste that good because of the variety from which they were developed. There was very little flavor to save,” said Christ Watkins, a horticulture professor at Cornell University. (credit:File/Flickr: Mr. T in DC)
(05 of05)
Open Image Modal
CLICK HERE to continue on to Mother Nature Network to see the rest of these bizarre genetically engineered creations, including banana vaccines, less-flatulent cows, medicinal eggs and more!
Suggest a correction
|
Submit a tip