Disease-specific cells developed by the Allen Institute for Cell Science offer a new window into the world's most common genetic heart condition.
Why it matters: Hypertrophic cardiomyopathy (HCM) — which affects an estimated 600,000 to 1.5 million Americans or 1 in 500 people — involves mutations that can cause heart muscle to thicken and other changes to the heart's mitral valves and cells.
Ancient grains of zircon crystals contain evidence suggesting dry land and freshwater may have existed on Earth 4 billion years ago, scientists report.
Why it matters: Some scientists consider freshwater and dry land to be prerequisites for the emergence of life on Earth — which fossil evidence indicates happened about 3.5 billion years ago.
