Understanding Genetics of Congenital Heart Defects through Individuals with Down Syndrome

          Down syndrome is the most common chromosome abnormality which there is a partial or full third copy of Chromosome 21. One of the unnoticed risks that individuals with Down syndrome experience is a high chance of congenital heart defects. Although half of those who have Down syndrome have structurally normal hearts it is still noticeably a high risk for one with Down syndrome to have a congenital heart defect.  Researchers at Emory University School of Medicine evaluated the changes in genes involved on and off of Chromosome 21 which are involved in abnormal heart development.  Their findings included that Down syndrome infants with congenital heart defects were more likely to have rare, large genetic deletions. The deletions which were observed tended to involve genes which affected cilia. The findings suggest that for those with Down syndrome the risk for congenital heart defects can come from several genes and environmental factors, in addition to the substantial risk from the extra chromosome 21.

Michael Zwick, PhD, associate professor of human genetics and pediatrics at Emory, has hopes that "Studying congenital heart defects in the 'at risk' Down syndrome population can make it possible to reveal genes that impact the risk of heart defects in all children, including those with typical number of chromosomes." Other than discovering the genes that affect congenital heart defects Zwick also hopes to perform more research on those with Down syndrome with hopes to establish what effects alterations in Chromosome 21  has on other organs in the body.

The risk of AVSD is higher in children with Down syndrome. An atrioventricular septal defect (AVSD) means that the central region of the heart separating the atria from the ventricles has failed to form properly.

This article was particularly interesting to me because I had a basic understanding of Down syndrome and was interested to learn more. I knew the mental disabilities which often accompany it but was uncertain what other changes were present in those who have Down syndrome. The article was interesting and educational for me as I was not familiar with Down Syndrome or congenital heart defects. 

Article: http://www.sciencedaily.com/releases/2014/10/141025152706.htm
Related Article: http://loonylabs.org/2014/10/24/congenital-heart-defects/