One faulty gene copy can make the heart’s DNA fold the wrong way

Researchers have discovered that a gene linked to congenital heart disease acts like an architect for the heart cell’s DNA. Losing just one copy of TBX5 can cause the genome’s carefully folded 3D structure to unravel, disrupting the genes needed to build a healthy heart. The effects can vary from cell to cell, which may help explain why people with the same mutation develop different heart defects. The same hidden mechanism could also play a role in other birth defects.