Peeking at huntingtin and learning from a PET study

Publication date: Jul 04, 2025

The recent study, called iMagemHTT, tested the tracer in 12 people with HD (who have expanded HTT in their brains) and 12 people without HD (who do not). A recent publication discusses a non-invasive way of measuring levels of expanded HTT protein in the brain, using an imaging tool called a PET tracer. When they analyzed the image data in this way, the expanded HTT ligand did bind more in people with HD compared to people without. Even in people without HD, who have no expanded HTT in their brains, there will be some tracer that grabs onto other proteins and shows up on the screen. In this HD study, the ligand was designed to stick to clumps of the expanded HTT protein. Its not clear exactly how well levels of expanded HTT from CSF reflect levels inside of brain cells. Known as aggregates, they contain bits of expanded HTT protein and other debris.