The condition known as hypertrophic cardiomyopathy, or HCM, is inherited and can be a killer. But some of the genetic mutations once thought linked to the illness are actually harmless, geneticists say.
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Exercise physiologist Courtney Conners checks Mario Oikonomides' vital signs before his cardiac rehab workout at the University of Virginia Health System clinic.
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Linda Johns (lower row, center), in the first moments of her heart attack. She's with fellow authors Kristen Kittscher, Kirby Larson, Suzanne Selfors, Sara Nickerson and Jennifer Longo at Queen Anne Book Co. in Seattle.
Courtesy of Linda Johns