Huntington disease is caused by a mutation in a gene that encodes a protein named what?

• A. Huntingtin
• B. Hemoglobin
• C. Myoglobin
• D. Collagen

Answer: (A)

Huntington disease is specifically linked to a mutation in the gene that encodes the protein known as huntingtin. This protein plays a crucial role in neuronal function and development. The mutation associated with Huntington disease involves an expansion of CAG repeats in the huntingtin gene, which leads to the production of a misfolded version of the huntingtin protein. This altered protein can form aggregates that are toxic to neurons, ultimately resulting in the neurodegenerative symptoms characteristic of Huntington disease. Other proteins listed, such as hemoglobin, myoglobin, and collagen, have completely different functions and are associated with other conditions and processes in the body. Hemoglobin carries oxygen in red blood cells, myoglobin serves a similar function in muscle tissues, and collagen is a structural protein important for the integrity of various tissues, none of which relate to Huntington disease.