The protein, α-synuclein, playsan incompletely specifiedrole in neurotransmitter release in brain neurons.1 Dysfunction is associated with Parkinson’s disease(PD) pathology in humans and animal models.2 Human α-synuclein is encoded by the SNCA gene and comprises140 amino acids (14.5 kDa). The gene discussed is SNCA; the disease is Parkinson disease.