Beginning in 1996, Donna Arnett, principal investigator of the University of Minnesota echocardiographic center under R01HL55673 , is performing a targeted echocardiographic exam on 3,100 HyperGEN participants in five field centers as part of the HyperGEN clinical examination. She is examining the genetics of left ventricular hypertrophy. Her study characterizes left ventricular structure and function, defines left ventricular structural phenotypes based on four geometric patterns (normal geometry, concentric remodeling, concentric left ventricular hypertrophy, and eccentric left ventricular hypertrophy). She examines a highly select group of candidate genes and their association with left ventricular mass and geometric pattern. Using quantitative trait loci analyses, she is testing for linkage of 240 anonymous, evenly spaced genetic markers with left ventricular mass and geometric patterns. She is also evaluating interactions between genes and potential risk factors for left ventricular hypertrophy, including insulin, glucose, blood pressure response to mental and physical stressors, dietary and urinary electrolytes, and obesity. The grant was not part of the original initiative. Approximately $2,093,000 support will be provided for this grant, broken down as follows: FY 1996 - $652,085; FY 1997 - $628,979; FY 1998 - $433,000; FY 1999 - $379,000.