DNA changes during pregnancy persist into childhood

September 4, 2013

Even before they are born, babies accumulate changes in their DNA through a process called DNA methylation that may interfere with gene expression, and in turn, their health as they grow up. But until now it's been unclear just how long these changes during the prenatal period persist. In a new study, researchers at the Columbia Center for Children's Environmental Health at the Mailman School of Public Health establish that signs of DNA methylation persist through early childhood, suggesting the factors that influence these changes during or before pregnancy could have effects throughout a child's life.

The study, published in an online edition of PLOS ONE, is the first to look at DNA methylation changes over time in children.

"The current dogma is that DNA methylation marks are set during early development and are mainly persistent thereafter. However, there were no data in humans to either support or refute this hypothesis. We set out to fill this data gap," explains lead author Julie Herbstman, PhD, assistant professor of Environmental Health Sciences at the Mailman School.

Recent evidence points to like arsenic, lead, and air pollution as factors in —the umbrella term for DNA methylation and other alterations to that don't come from DNA mutations. While the of small changes in DNA methylation is not yet clear, there is concern that alterations caused by environmental exposures during important periods of development that could have effects across a lifetime. Generally, low levels of global DNA methylation have been linked to genomic instability, which can lead to DNA damage. (Global DNA methylation is defined as methylation levels measured in aggregate for all genetic material, not specific to one or more genes.)

Center researchers analyzed global DNA methylation levels in blood at two different time points. Cord blood was analyzed from 279 children who are part of the Center's Mothers & Newborns study in Northern Manhattan and the South Bronx. Of these children, 165 also had blood collected at age 3.

The authors found that cord blood methylation was correlated with and significantly predicted the level of methylation at 3 years old. This supports the hypothesis that DNA methylation changes occurring early in life may have lasting impacts.

Maternal BMI Affects Levels of DNA Methylation

The researchers examined one specific factor to see how it affected DNA methylation in children—the mother's body mass index prior to becoming pregnant. Children born to moms with high BMIs had low levels of global DNA methylation, an association that was seen again at age 3.

The new study provides further evidence that maternal factors like BMI prior to pregnancy can lead to molecular changes on an epigenetic level. The observation that these same factors continue to impact DNA methylation in blood at age 3 raises concern about the potential for pre-pregnancy and prenatal conditions to have lasting health effects. The association between pre-pregnancy BMI and decreased global DNA methylation is of particular interest given the high proportion of obesity among women of reproductive age.

The findings point to a need for further research to understand how factors, such as high BMI before pregnancy, could influence the trajectory of a child's health. "Understanding whether and how maternal characteristics and environmental factors during early development impact long-term child health is a critical first step in identifying targets for disease prevention," says Dr. Herbstman.

Explore further: Deciphering the cellular reading system of DNA methylation

Related Stories

Deciphering the cellular reading system of DNA methylation

April 12, 2013
(Medical Xpress)—Scientists from the FMI identify how a family of proteins reads the methylation marks on the DNA so critical for cell development. These MBD proteins bind directly to methylation marks and inactivate the ...

Maternal glycemic status linked to epigenetic changes

March 9, 2012
(HealthDay) -- Maternal glycemic status and adiponectin levels are linked to epigenetic changes in the adiponectin gene (ADIPOQ), according to a study published online March 6 in Diabetes.

Experts find epigenetic changes moderate reality distortion in schizophrenia patients

June 10, 2013
A study in Schizophrenia Bulletin is among the first to indicate epigenetic changes related to immune function in schizophrenia. DNA methylation, a process involving the addition of a methyl group to the DNA without changing ...

Maternal smoking causes changes in fetal DNA

May 18, 2011
Children whose mothers or grandmothers smoked during pregnancy are at increased risk of asthma in childhood, but the underlying causes of this are not well understood. Now a new study indicates changes in a process called ...

New insights into why humans are more susceptible to cancer and other diseases

August 23, 2012
Chimpanzees rarely get cancer, or a variety of other diseases that commonly arise in humans, but their genomic DNA sequence is nearly identical to ours. So, what's their secret? Researchers reporting in the September issue ...

Epigenetics mechanism may help explain effects of mom's nutrition on her children's health

March 11, 2013
Pioneering studies by U. S. Department of Agriculture-funded research molecular geneticist Robert A. Waterland are helping explain how the foods that soon-to-be-moms eat in the days and weeks around the time of conception—or ...

Recommended for you

Scientists provide insight into genetic basis of neuropsychiatric disorders

July 21, 2017
A study by scientists at the Children's Medical Center Research Institute at UT Southwestern (CRI) is providing insight into the genetic basis of neuropsychiatric disorders. In this research, the first mouse model of a mutation ...

Scientists identify new way cells turn off genes

July 19, 2017
Cells have more than one trick up their sleeve for controlling certain genes that regulate fetal growth and development.

South Asian genomes could be boon for disease research, scientists say

July 18, 2017
The Indian subcontinent's massive population is nearing 1.5 billion according to recent accounts. But that population is far from monolithic; it's made up of nearly 5,000 well-defined sub-groups, making the region one of ...

Mutant yeast reveals details of the aberrant genomic machinery of children's high-grade gliomas

July 18, 2017
St. Jude Children's Research Hospital biologists have used engineered yeast cells to discover how a mutation that is frequently found in pediatric brain tumor high-grade glioma triggers a cascade of genomic malfunctions.

Late-breaking mutations may play an important role in autism

July 17, 2017
A study of nearly 6,000 families, combining three genetic sequencing technologies, finds that mutations that occur after conception play an important role in autism. A team led by investigators at Boston Children's Hospital ...

Newly discovered gene variants link innate immunity and Alzheimer's disease

July 17, 2017
Three new gene variants, found in a genome wide association study of Alzheimer's disease (AD), point to the brain's immune cells in the onset of the disorder. These genes encode three proteins that are found in microglia, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.