The selective neuronal dysfunction and subsequent cell death in HD is now thought to be the result of a multifactorial etiology that includes transcriptional dysregulation, excitotoxicity, altered energy metabolism, impaired axonal transport of mitochondria, and synaptic degeneration
HD adversely affects neurotransmitter levels, resulting in decreased acetylcholine and gamma aminobutyric acid (GABA) and increased dopamine levels.