Congenital Heart disease (CHD) is the defect that occurs in the heart of child right from its birth due to genetic deformity. This could affect any structural part of the Heart such as the walls, valves, arteries, veins etc. CHD being one the most common birth defects has been statistically analyzed to affect 1 in every 100 children. It is also one of the leading causes of mortality from birth defects.
Abnormality in the heart that develops before birth
A new study from the NHLBI Pediatric Cardiac Genomics Consortium (PGCG), part of the Bench to Bassinet Program, has discovered the basic genetic causes behind the CHD and has also offered some long-term outlook for patients who carry these mutations. The researchers had understood that detection of these mutations alert patients and parents to know the risk of ongoing problems that can be addressed and managed. Parents might also be able to foresee similar risks in their second child too.
This study was conducted in collaboration with researchers at seven academic centers across the U.S., leverages clinical and genetic data from more than 2,800 patients with CHD as well as information from parents. This allowed the researchers to determine which genetic mutations had been passed from parents to offspring and which had appeared spontaneously in the child’s genome (known as de novo mutations).
Findings regarding the genetic mutations are transmitted from parents to children:
- Mutations in one gene, FLT4, that consistently led to a condition known as Tetralogy of Fallot, a complex malformation that often presents with cyanosis or “Blue baby syndrome.”
- Mutations in the gene encoding Myosin, a contractile protein that is highly expressed during development accounted for about 11 percent of Shone syndrome affecting four regions of the left-side of the heart.
- Identical mutation in both gene copies of GDF1 accounted for approximately 5 percent of severe CHD among children of Ashkenazian descent could have direct clinical implications for assessing risk among people with this ancestry.
Findings regarding the mutations appear for the first time (de novo mutations) in a child’s genome:
- De novo mutations in many genes, particularly in those that modify chromatin, a complex material that surrounds DNA and that undergoes dynamic changes during development.
- These mutations occurred most often in CHD children than other congenital defects or neurodevelopmental issues. Notably, these same genes have been previously associated with autism, which may account for high rates of neurocognitive issues in some children with CHD.
Thus, this basic discovery provides a clear pathway for the futuristic findings of CHD related genetic defects.
Future direction
- From the above studies it has already been indicated that as many as 400 genes contribute to the CHD.
- Whole-genome sequencing is expected to be the most effective way to detect genetic variants that cause birth defects than screening for specific mutations.
References:
- Warburton, D., Ronemus, M., Kline, J., Jobanputra, V., Williams, I., Anyane-Yeboa, K., . . . Levy, D. (2013). The contribution of de novo and rare inherited copy number changes to congenital heart disease in an unselected sample of children with conotruncal defects or hypoplastic left heart disease. Human Genetics, 133(1), 11-27. doi:10.1007/s00439-013-1353-9
- Study sheds new light on underlying genetic causes of congenital heart disease. (2017, October 09). Retrieved October 13, 2017, from https://www.news-medical.net/news/20171009/Study-sheds-new-light-on-underlying-genetic-causes-of-congenital-heart-disease.aspx
- Default – Stanford Children’s Health. (n.d.). Retrieved October 13, 2017, from http://www.stanfordchildrens.org/en/topic/default?id=factors-contributing-to-congenital-heart-disease-90-P01788
- Richards, A. A., & Garg, V. (2010). Genetics of Congenital Heart Disease. Current Cardiology Reviews, 6(2), 91-97. doi:10.2174/157340310791162703
- (n.d.). Retrieved October 13, 2017, from https://g.co/kgs/iDUuJr
