cystic fibrosis

About 100,000 people in the United States have sickle cell disease, and most of them are African-American. While there is effective care for the disease, it's difficult for patients to obtain.

Why do some people get sick from genetic mutations and others don't? Scientists say clues may lie in a rare group of people who carry profound genetic defects but somehow don't fall ill.

The success of Kalydeco, a drug to treat cystic fibrosis, has been decades in the making — since the discovery of the gene associated with the disease. The time from gene discovery to successful drug may be shortening, but there are only a handful of drugs like Kalydeco on the market.