Project 1, Project 2 Eric Olson, Ph.D. Signaling Pathways to LVH Myocardial Regeneration and Stem Cell Biology   Project 3 Helen H. Hobbs, M.D. Genetics of CHD Risk The Dallas Heart Study COHORT Link

Research Developments A Common Allele on Chromosome 9 Associated with Coronary Heart Disease.   Coronary heart disease (CHD) is a major cause of death in Western countries. Here we used genome-wide association scanning to identify a 58 kilobase interval on chromosome 9p21 that was consistently associated with CHD in six independent samples (n> 23,000 participants) from four Caucasian populations. This interval, which is located near the CDKN2A and CDKN2B genes, contains no annotated genes and is not associated with established CHD risk factors such as plasma lipoproteins, hypertension or diabetes. Homozygotes for the risk allele comprise 20-25% of Caucasians and have a ~30-40% increased risk of CHD.. See the full publication in the May 2007 Science (Science 2007 May 3) In Press.

Control of Stress-Dependent Cardiac Growth and Gene Expression by a MicroRNA.   The heart responds to diverse forms of stress by hypertrophic growth accompanied by fibrosis and eventual diminution of contractility, which results from down-regulation of  myosin heavy chain (MHC) and up-regulation of ßMHC, the primary contractile proteins of the heart. We found that a cardiac-specific microRNA (miR-208) encoded by an intron of the MHC gene is required for cardiomyocyte hypertrophy, fibrosis, and expression of ßMHC in response to stress and hypothyroidism. Thus, the MHC gene, in addition to encoding a major cardiac contractile protein, regulates cardiac growth and gene expression in response to stress and hormonal signaling through miR-208. See the full publication in the April 2007 Science. (Science 2007 April 27) In Press.