SNCA and Parkinson disease: The underlined pathology of PD involves the loss of dopaminergic neurons in a basal ganglia structure of the human brain (i.e., substantia nigra) and the presence of a widely distributed Lewy body containing, alpha-synuclein protein in the brain3, substantiating a prodromal period of PD with the presence of non-motor symptoms related with the olfactory system and the gut4.