Genetics of Hypoplastic Left Heart Syndrome

Doctor's Name: 
Vidu Garg, M.D.
Hospital/Institution: 
University of Texas Southwestern Medical Center

Congenital heart disease is the most common type of birth defect but the cause for the majority of cardiac birth defects remains unknown. Dr. Garg and associates have discovered a few genetic causes of human congenital heart disease by traditional genetic approaches, which require identification of multi-generational families with several affected family members. This approach to identify novel genetic etiologies is limited by the scarcity of suitable pedigrees and to mild forms of congenital heart disease since severe heart defects are often lethal in childhood. One of the most severe types of congenital heart disease occurs when the left ventricle fails to develop properly, termed, hypoplastic left heart syndrome ( HLHS ). This research proposes to identify novel genetic etiologies of HLHS, by using a new technology, whole-genome array comparative genomic hybridization ( CGH ). Whole-genome array CGH is a high-throughput method made possible by the Human Genome Project that can detect small abnormalities within a person’s entire genetic material, such as extra or missing chromosomal DNA ( deoxyribonucleic acid ). Dr. Garg and associates hypothesize that a subset of children with HLHS have chromosomal abnormalities that are not detected by currently available genetic testing. In brief, DNA will be extracted from the blood collected from children with HLHS and analyzed by the Whole-Genome Array CGH using a commercial platform ( Nimblegen ). This research will allow researchers to determine the frequency of cryptic genetic abnormalities in children with HLHS. Identification of novel submicroscopic deletions or duplications in these children will accelerate the discovery of genetic causes of HLHS. These findings will have important diagnostic and therapeutic consequences for these children.

Award Date 1: 
2007
Award Amount 1: 
$70,000
Award Date 2: 
2008
Award Amount 2: 
$70,000