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

New Insights into How Genes Turn On and Off

Published: Thursday, March 28, 2013
Last Updated: Thursday, March 28, 2013
Bookmark and Share
Researchers at UC Davis and the University of British Columbia have shed new light on methylation, a critical process that helps control how genes are expressed.

Working with placentas, the team discovered that 37 percent of the placental genome has regions of lower methylation, called partially methylated domains (PMDs), in which gene expression is turned off. This differs from most human tissues, in which 70 percent of the genome is highly methylated.

While PMDs have been identified in cell lines, this is the first time they have been found in regular human tissue. In addition to enhancing our understanding of epigenetics, this work could influence cancer research and help illuminate how environmental toxins affect fetal development. The paper was published online this week in the Proceedings of the National Academy of Sciences (PNAS).

Since it was unraveled more than ten years ago, the human genome has been the focus of both popular interest and intense scientific focus. But the genome doesn't act alone; there are many factors that influence whether genes are turned on or off. One of these is an epigenetic process called methylation, in which a group of carbon and hydrogen atoms (a methyl group) attaches to DNA, adjusting how genes are expressed.

"I like to think of epigenetics as a layer on top of your genetic code," said senior author Janine LaSalle, professor of medical microbiology and immunology. "It's not the DNA sequence but it layers on top of that - and methylation is the first layer. Those layers provide a lot of information to the cells on where and when to turn on the genes."

How and when genes are activated (or inactivated) can have a profound impact on human development, cancer and the biological legacy of environmental toxins. Prior to this research, PMDs had only been found in cultured cell lines, which led some scientists to wonder if they existed outside the test tube. This study confirms they exist in placental tissue, a critically important window into fetal development.

"The placenta is the interface between mother and fetus," said LaSalle, who is a researcher affiliated with the UC Davis MIND Institute. "It's a time capsule from when a lot of important methylation events occurred."

In addition, placental tissue was interesting to study because it has a number of invasive characteristics often associated with cancer. In fact, a number of cancers, such as breast and colon, have widespread PMDs. LaSalle notes that anti-cancer epigenetic therapies that adjust methylation could be refined based on this improved understanding of PMDs.

This work could also enhance our ability to detect genetic defects. Methylation, and other epigenetic data, provides information that cannot be found in the genome alone. For example, the vast majority of cells in the body contain identical genetic code. However, the added information provided by methylation allows scientists to determine where specific DNA came from.

"Methylation patterns are like fingerprints, showing which tissue that DNA is derived from," LaSalle said. "You can't get that information from just the DNA sequence. As a result, methylation studies could be a very rich source for biomarkers."

In the study, PMDs encompassed 37 percent of the placental genome, including 3,815 genes, around 17 percent of all genes. When found in low-methylation regions, these genes were less likely to be transcribed into proteins. Researchers also found that PMDs also contain more highly methylated CpG islands (genomic areas with large numbers of cytosine-guanine pairs), which are often associated with gene transcriptional silencing of promoters.

Because the placental PMDs contained many genes associated with neuronal development, and specifically autism, LaSalle notes that future research could investigate how epigenetics impacts autism genes at birth.

"We are looking for biomarkers that predict neurodevelopmental outcomes," LaSalle said. "Now we have a series of snap shots from a critical period where we think environmental factors are playing a role in the developing brain."


Further Information

Join For Free

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 2,900+ scientific posters on ePosters
  • More than 4,200+ 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

Crowdfunding the Fight Against Cancer
From budding social causes to groundbreaking businesses to the next big band, crowdfunding has helped connect countless worthy projects with like-minded people willing to support their efforts, even in small ways. But could crowdfunding help fight cancer?
Monday, February 08, 2016
Science Magazine Names CRISPR ‘Breakthrough of the Year’
In its year-end issue, the journal Science chose the CRISPR genome-editing technology invented at UC Berkeley 2015’s Breakthrough of the Year.
Monday, December 21, 2015
CRISPR-Cas9 Helps Uncover Genetics of Exotic Organisms
A new study illustrates the ease with which CRISPR-Cas9 can knock out genes in exotic animals to learn how those genes control growth and development.
Friday, December 11, 2015
New Method for Screening Cancer Cells
Parallel microfiltration could lead to better treatments for a number of diseases, UCLA-led study says.
Thursday, December 03, 2015
RNA-Based Drugs Give More Control Over Gene Editing
CRISPR/Cas9 gene editing technique can be transiently activated and inactivated using RNA-based drugs, giving researchers more precise control in correcting and inactivating genes.
Monday, November 23, 2015
Clearest Ever Images of Enzyme that Plays Key Roles in Aging, Cancer
UCLA-led research on telomerase could lead to new strategies for treating disease
Monday, October 19, 2015
Crop Cure
Scientists in new center to use medical research techniques to help food crops withstand drought and climate change.
Friday, October 16, 2015
Rare Childhood Leukemia Reveals Surprising Genetic Secrets
A coalition of leukemia researchers led by scientists from UC San Francisco has discovered surprising genetic diversity in juvenile myelomonocytic leukemia (JMML), a rare but aggressive childhood blood cancer.
Thursday, October 15, 2015
Double Enzyme Hit May Explain Common Cancer Drug Side Effect
Mouse study suggests genomic screening before treatment may help prevent anemia.
Wednesday, October 14, 2015
New Autism Genes Are Revealed in Largest-Ever Study
Work draws more detailed picture of genetic risk, sheds light on sex differences in diagnosis.
Wednesday, September 30, 2015
Scientists Create CRISPR/Cas9 Knock-In Mutations in Human T Cells
In a project spearheaded by investigators at UC San Francisco, scientists have devised a new strategy to precisely modify human T cells using the genome-editing system known as CRISPR/Cas9.
Tuesday, July 28, 2015
Simple Technology Makes CRISPR Gene Editing Cheaper
University of California, Berkeley, researchers have discovered a much cheaper and easier way to target a hot new gene editing tool, CRISPR-Cas9, to cut or label DNA.
Friday, July 24, 2015
Engineers Crack DNA Code of Autoimmune Disorders
Researchers have identified an unexpectedly general set of rules that determine which molecules can cause the immune system to become vulnerable to the autoimmune disorders lupus and psoriasis.
Wednesday, June 10, 2015
Genetic Markers for Detecting and Treating Ovarian Cancer
Custom bioinformatics algorithm identifies human mRNAs that distinguish ovarian cancer cells from normal cells and provide new therapeutic targets
Wednesday, May 27, 2015
Industry-Sponsored Academic Inventions Spur Increased Innovation
Analysis questions assumption that corporate support skews science toward inventions that are less useful than those funded by the government or non-profit organizations.
Monday, March 24, 2014
Scientific News
NIH Researchers Identify Striking Genomic Signature for Cancer
Institute has identified striking signature shared by five types of cancer.
CRI Develops Innovative Approach for Identifying Lung Cancer
Institute has developed innovative approach for identifying processes that fuel tumor growth in lung cancer patients.
The Spice of Life
Scientists discover important genetic source of human diversity.
Removing Race from Human Genetic Research
A group of scientists are urging their colleagues to take a step forward and stop using racial categories when researching and studying human genetics.
Light Signals from Living Cells
Fluorescent protein markers delivered under high pressure.
Counting Cancer-busting Oxygen Molecules
Researchers from the Centre for Nanoscale BioPhotonics (CNBP), an Australian Research Centre of Excellence, have shown that nanoparticles used in combination with X-rays, are a viable method for killing cancer cells deep within the living body.
Genomic Signature Shared by Five Types of Cancer
National Institutes of Health researchers have identified a striking signature in tumor DNA that occurs in five different types of cancer.
Crowdfunding the Fight Against Cancer
From budding social causes to groundbreaking businesses to the next big band, crowdfunding has helped connect countless worthy projects with like-minded people willing to support their efforts, even in small ways. But could crowdfunding help fight cancer?
Switch Lets Salmonella Fight, Evade Immune System
Researchers at the University of Illinois at Chicago have discovered a molecular regulator that allows salmonella bacteria to switch from actively causing disease to lurking in a chronic but asymptomatic state called a biofilm.
Genetic Cause of Rare Allergy
Institute has identified a genetic mutation responsible for a rare form of inherited hives induced by vibratory urticaria.
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
2,900+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,200+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!