| Motor symptoms | Chorea (involuntary movements), dystonia, bradykinesia |
| Cognitive symptoms | Executive dysfunction, memory deficits, impaired judgment |
| Psychiatric symptoms | Depression, anxiety, irritability, psychosis |
| Neuronal development | Embryonic neurogenesis |
| Synaptic function | Vesicle trafficking, neurotransmitter release |
| Transcriptional regulation | Supporting neuronal survival |
| Axonal transport | Organelle and protein trafficking |
| [Autophagy](/entities/autophagy) | Cellular quality control |
| Normal | < 27 CAG repeats |
| Intermediate | 27-35 repeats (not disease-causing but can expand in offspring) |
| Reduced penetrance | 36-39 repeats (may or may not cause disease) |
| Full penetrance | ≥ 40 repeats (will develop HD) |
| Databases | OMIMOrphanetClinicalTrialsPubMed |