New mouse model helps explain gene discovery in congenital heart disease

June 26, 2012

Scientists now have clues to how a gene mutation discovered in families affected with congenital heart disease leads to underdevelopment of the walls that separate the heart into four chambers. A Nationwide Children's Hospital study appearing in PLoS Genetics suggests that abnormal development of heart cells during embryogenesis may be to blame.

When babies are born with a hole in their heart (either between the upper or lower chambers), they have a septal defect, the most common form of . Although it's not clear what causes all septal defects, genetic studies primarily utilizing large families have led to the discovery of several .

Vidu Garg, MD, the study's lead author, previously reported that a single nucleotide change in the GATA4 gene in humans causes atrial and ventricular septal defects along with pulmonary valve stenosis. In mice, the GATA4 gene has been shown to be necessary for normal heart development and its deletion leads to abnormal heart development.

"While GATA4 has been shown to be important for several critical processes during early heart formation, the mechanism for the heart malformations found in humans with the mutation we previously reported is not well understood," said Dr. Garg, a pediatric cardiologist in The Heart Center and principal investigator in the Center for Cardiovascular and Pulmonary Research at The Research Institute at Nationwide Children's Hospital.

To better characterize the mutation, Dr. Garg and colleagues generated a mouse model harboring the same human disease-causing mutation. They saw heart abnormalities in the mice that were consistent with those seen in humans with GATA4 mutations. Upon further examination, they found that the mutant protein leads to functional deficits in the ability for to increase in number during embryonic development.

"Our findings suggest that cardiomyocyte proliferation deficits could be a mechanism for the septal defects seen in this mouse model and may contribute to septal defects in humans with mutations in GATA4," said Dr. Garg, also a faculty member at The Ohio State University College of Medicine. "This mouse model will be valuable in studying how septation and heart valve defects arise and serve as a useful tool to study the impact of environmental factors on GATA4 functions during ."

Explore further: Study identifies second gene associated with specific congenital heart defects

Related Stories

Study identifies second gene associated with specific congenital heart defects

April 29, 2011
A gene known to be important in cardiac development has been newly associated with congenital heart malformations that result in obstruction of the left ventricular outflow tract. These are the findings from a study conducted ...

Recommended for you

New gene editing approach for alpha-1 antitrypsin deficiency shows promise

October 20, 2017
A new study by scientists at UMass Medical School shows that using a technique called "nuclease-free" gene editing to correct cells with the mutation that causes a rare liver disease leads to repopulation of the diseased ...

Maternal diet may program child for disease risk, but better nutrition later can change that

October 20, 2017
Research has shown that a mother's diet during pregnancy, particularly one that is high-fat, may program her baby for future risk of certain diseases such as diabetes. A new study from nutrition researchers at the University ...

Researchers find evidence of DNA damage in veterans with Gulf War illness

October 19, 2017
Researchers say they have found the "first direct biological evidence" of damage in veterans with Gulf War illness to DNA within cellular structures that produce energy in the body.

Researchers drill down into gene behind frontotemporal lobar degeneration

October 19, 2017
Seven years ago, Penn Medicine researchers showed that mutations in the TMEM106B gene significantly increased a person's risk of frontotemporal lobar degeneration (FTLD), the second most common cause of dementia in those ...

New clues to treat Alagille syndrome from zebrafish

October 18, 2017
A new study led by researchers at Sanford Burnham Prebys Medical Discovery Institute (SBP) identifies potential new therapeutic avenues for patients with Alagille syndrome. The discovery, published in Nature Communications, ...

Genetic variants associated with obsessive-compulsive disorder identified

October 18, 2017
(Medical Xpress)—An international team of researchers has found evidence of four genes that can be linked to obsessive-compulsive disorder (OCD). In their paper published in the journal Nature Communications, the group ...

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.