Which method is used to confirm Huntington's disease?

• A. Genetic testing
• B. CT/MRI shows brain atrophy with enlarged ventricles
• C. EEG
• D. Bone scan

Answer: (A)

The defining way to confirm Huntington's disease is by genetic testing that detects an expanded CAG repeat in the HTT gene. This genetic finding provides definitive proof of the disease, since the pathogenic repeat expansion leads to Huntington's and can be identified even before symptoms appear in at-risk individuals. Imaging studies like CT or MRI may show characteristic brain changes (such as caudate atrophy with ventricular enlargement) and can support a clinical suspicion, but they are not diagnostic on their own. EEG and bone scans don’t offer diagnostic confirmation for Huntington's.