Nonsense-mediated decay

Nonsense-mediated decay (NMD) is a natural quality control process in cells that prevents the production of faulty proteins. When a gene is copied into messenger RNA (mRNA), sometimes errors create a premature stop signal—called a "nonsense" mutation—that would lead to incomplete, potentially harmful proteins. NMD detects these abnormal mRNAs and quickly destroys them before they can be used to make proteins. This ensures that only correct, functional proteins are produced, maintaining cell health and function.