Corporate Banner
Satellite Banner
Genomics
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Epigenetic Clock Marks Age of Human Tissues and Cells

Published: Tuesday, November 05, 2013
Last Updated: Tuesday, November 05, 2013
Bookmark and Share
The age of many human tissues and cells is reflected in chemical changes to DNA. The finding provides insights for cancer, aging, and stem cell research.

We may gauge how we’re aging based on visible changes, such as wrinkles. For years, scientists have been trying to gauge aging based on changes inside our cells.

Many alterations occur to our DNA as we age. Some of these changes are epigenetic—they modify DNA without altering the genetic sequence itself. These changes affect how cells in different parts of the body use the same genetic code. By controlling when specific genes are turned on and off, or “expressed,” they tell cells what to do, where to do it, and when to do it.

One such type of modification occurs when chemical tags known as methyl groups attach to DNA in specific places. This process, known as methylation, affects interactions between DNA and protein-making machinery. Changes in DNA methylation—both increases and decreases—occur with aging.

Dr. Steve Horvath from the University of California, Los Angeles, examined the relationship between DNA methylation and aging. He took advantage of publicly available methylation datasets, including ones from The Cancer Genome Atlas, a joint effort of NIH’s National Cancer Institute (NCI) and National Human Genome Research Institute (NHGRI). The datasets were developed by hundreds of researchers and comprised almost 8,000 samples of 51 healthy tissues and cell types. Samples came from people ranging in age from newborns to 101 years. They included tissues from throughout the body, including the brain, breast, skin, colon, kidney, liver, lung, and heart.

Horvath first developed an age predictor using 39 datasets. The tool was based on 353 specific DNA sites where methyl groups increased or decreased with age. He then tested the predictor in 32 additional datasets. Results appeared in the October 21, 2013, issue of Genome Biology.

Horvath found that the computed biological age based on DNA methylation closely predicted the chronological age of numerous tissues and cells to within just a few years. There were some tissues, however, where the biological age did not match the chronological age. These included skeletal muscle, heart tissue, and breast tissue. The clock also worked well in chimpanzees.

In both embryonic and induced pluripotent stem cells—genetically altered adult cells with characteristics of embryonic stem cells—the DNA methylation age proved to be near zero.

Horvath also analyzed nearly 6,000 samples from 20 different cancers and found that cancer greatly affected DNA methylation age. However, in most cancers the age acceleration didn’t reflect the tumor grade and stage.

The rate of ticking of the biological clock, as measured by the rates of change in DNA methylation, wasn’t constant. It was faster from birth to adulthood, and then slowed to a constant rate around the age of 20.

Horvath didn’t find evidence of a relationship with DNA methylation age in B cells (a type of white blood cell) from people with a premature aging disease (progeria).

“Pinpointing a set of biomarkers that keeps time throughout the body has been a 4-year challenge,” Horvath says. “My goal in inventing this age-predictive tool is to help scientists improve their understanding of what speeds up and slows down the human aging process.”

UCLA has filed a provisional patent on the age-predictive tool, which is freely available to scientists online. Horvath plans to examine whether DNA methylation is only a marker of aging or itself affects aging.


Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,500+ scientific posters on ePosters
  • More than 3,700+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Cellular Factors that Shape the 3D Landscape of the Genome Identified
Researchers have identified 50 cellular factors required for the proper 3D positioning of genes by using novel large-scale imaging technology.
Tuesday, August 18, 2015
Nuclear Process in the Brain That May Affect Disease Uncovered
Scientists have shown that the passage of molecules through the nucleus of a star-shaped brain cell, called an astrocyte, may play a critical role in health and disease.
Tuesday, August 18, 2015
Tell-tale Biomarker Detects Early Breast Cancer in NIH-funded Study
The study published online in the issue of Nature Communications.
Thursday, August 13, 2015
Scientists Adopt New Strategy to Find Huntington’s Disease Therapies
Large, international NIH-supported study uses precision medicine to tackle neurological disorders.
Tuesday, August 11, 2015
Study Shows Promise of Precision Medicine for Most Common Type of Lymphoma
The study appeared online July 20, 2015, in Nature Medicine.
Tuesday, July 21, 2015
NIH Study Identifies Gene Variant Linked to Compulsive Drinking
Mice carrying the Met68BDNF gene variant would consume excessive amounts of alcohol.
Tuesday, July 21, 2015
In Blinding Eye Disease, Trash-Collecting Cells Go Awry, Accelerate Damage
NIH research points to microglia as potential therapeutic target in retinitis pigmentosa.
Friday, July 03, 2015
Potential Therapeutic for Blinding Eye Disease
NIH research points to microglia as potential therapeutic target in retinitis pigmentosa.
Thursday, July 02, 2015
NCI-MATCH Trial will Link Targeted Cancer Drugs to Gene Abnormalities
Precision medicine trial will open to patient enrollment in July.
Tuesday, June 09, 2015
A New Role for Zebrafish: Larger Scale Gene Function Studies
A relatively new method of targeting specific DNA sequences in zebrafish could dramatically accelerate the discovery of gene function and the identification of disease genes in humans.
Monday, June 08, 2015
NIH Researchers Pilot Predictive Medicine by Studying Healthy People’s DNA
New study sequence the genomes of healthy participants to find “putative,” or presumed, mutations.
Friday, June 05, 2015
Linking Targeted Cancer Drugs to Gene Abnormalities
Investigators at the NIH have announced a series of clinical trials that will study drugs or drug combinations that target specific genetic mutations.
Wednesday, June 03, 2015
Scientists Create Mice with a Major Genetic Cause of ALS and FTD
NIH-funded study provides new platform for testing treatments for several neurodegenerative disorders.
Friday, May 22, 2015
Mice With a Major Genetic Cause of ALS and FTD Created
NIH-funded study provides new platform for testing treatments for several neurodegenerative disorders.
Thursday, May 21, 2015
New Insights into How DNA Differences Influence Gene Activity, Disease Susceptibility
NIH-funded pilot study provides a new resource about variants across the human genome.
Friday, May 08, 2015
Scientific News
Poor Survival Rates in Leukemia Linked to Persistent Genetic Mutations
For patients with an often-deadly form of leukemia, new research suggests that lingering cancer-related mutations – detected after initial treatment with chemotherapy – are associated with an increased risk of relapse and poor survival.
Searching Big Data Faster
Theoretical analysis could expand applications of accelerated searching in biology, other fields.
Growing Hepatitis C in the Lab
Recent discovery allows study of naturally occurring forms of hepatitis C virus (HCV) in the lab.
Inciting an Immune Attack on Cancer Cells
A new minimally invasive vaccine that combines cancer cells and immune-enhancing factors could be used clinically to launch a destructive attack on tumors.
Reprogramming Cancer Cells
Researchers on Mayo Clinic’s Florida campus have discovered a way to potentially reprogram cancer cells back to normalcy.
Genetic Overlapping in Multiple Autoimmune Diseases May Suggest Common Therapies
CHOP genomics expert leads analysis of genetic architecture, with eye on repurposing existing drugs.
Surprising Mechanism Behind Antibiotic-Resistant Bacteria Uncovered
Now, scientists at TSRI have discovered that the important human pathogen Staphylococcus aureus, develops resistance to this drug by “switching on” a previously uncharacterized set of genes.
How DNA ‘Proofreader’ Proteins Pick and Edit Their Reading Material
Researchers from North Carolina State University and the University of North Carolina at Chapel Hill have discovered how two important proofreader proteins know where to look for errors during DNA replication and how they work together to signal the body’s repair mechanism.
Fat in the Family?
Study could lead to therapeutics that boost metabolism.
Tissue Bank Pays Dividends for Brain Cancer Research
Checking what’s in the bank – the Brisbane Breast Bank, that is – has paid dividends for UQ cancer researchers.
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,700+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FREE!