Follow your heart

Third Rock provided newco MyoKardia Inc. with $38 million in series A money in hopes the biotech will parlay its founders' scientific insights about myosin, a key component of muscle contraction, into small molecules to treat genetic forms of heart disease.

"There are 5 million people in the U.S. with heart failure, but no genetic basis for understanding who is at risk," said Third Rock's Charles Homcy, who is interim CEO of MyoKardia...