Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Our genome changes over lifetime

26.06.2008
May explain many 'late-onset' diseases

Researchers at Johns Hopkins have found that epigenetic marks on DNA-chemical marks other than the DNA sequence-do indeed change over a person's lifetime, and that the degree of change is similar among family members.

Reporting in the June 25 issue of the Journal of the American Medical Association, the team suggests that overall genome health is heritable and that epigenetic changes occurring over one's lifetime may explain why disease susceptibility increases with age.

"We're beginning to see that epigenetics stands at the center of modern medicine because epigenetic changes, unlike DNA sequence which is the same in every cell, can occur as a result of dietary and other environmental exposure," says Andrew P. Feinberg, M.D., M.P.H, a professor of molecular biology and genetics and director of the Epigenetics Center at the Johns Hopkins School of Medicine. "Epigenetics might very well play a role in diseases like diabetes, autism and cancer."

... more about:
»DNA »epigenetic »methylation

If epigenetics does contribute to such diseases through interaction with environment or aging, says Feinberg, a person's epigenetic marks would change over time. So his team embarked on an international collaboration to see if that was true. They focused on methylation-one particular type of epigenetic mark, where chemical methyl groups are attached to DNA.

"Inappropriate methylation levels can contribute to disease-too much might turn necessary genes off, too little might turn genes on at the wrong time or in the wrong cell," says Vilmundur Gudnason, MD, PhD, professor of cardiovascular genetics at the University of Iceland director of the Icelandic Heart Association's Heart Preventive Clinic and Research Institute. "Methylation levels can vary subtly from one person to the next, so the best way to get a handle on significant changes is to study the same individuals over time."

The researchers used DNA samples collected from people involved in the AGES Reykjavik Study (formerly the Reykjavik Heart Study). Within the study, about 600 people provided DNA samples in 1991, and again between 2002 and 2005. Of these, the research team measured the total amount of DNA methylation in each of 111 samples and compared total methylation from DNA collected in 2002 to 2005 to that person's DNA collected in 1991.

They found that in almost one-third of individuals, methylation changed over that 11-year span, but not all in the same direction. Some individuals gained total methylation in their DNA, while others lost. "What we saw was a detectable change over time, which showed us proof of the principle that an individual's epigenetics does change with age," says M. Daniele Fallin, Ph.D., an associate professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health. "What we still didn't know was why or how, but we thought 'maybe this, too, is something that's heritable' and could explain why certain families are more susceptible to certain diseases."

The team then measured total methylation changes in a different set of DNA samples collected from Utah residents of northern and western European descent. These DNA samples were collected over a 16-year span from 126 individuals from two- and three-generation families.

Similar to the Icelandic population, the Utah family members also showed varied methylation changes over time. But they found that family members tended to have the same kind of change-if one individual lost methylation over time, they saw similar loss in other family members.

"We still haven't concretely figured out what this means for health and disease, but as an epidemiologist, I think this is very interesting, since epigenetic changes could be an important link between environment, aging and genetic risk for disease," Fallin says.

Audrey Huang | EurekAlert!
Further information:
http://www.jhmi.edu
http://www.hopkinsmedicine.org/ibbs/research/epigenetics/
http://jama.ama-assn.org/

Further reports about: DNA epigenetic methylation

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>