Clinical and pathological features of PD include a world-wide distribution, male predominance, a variable clinical presentation and progress, motor, non-motor and multisystem clinical involvement, a long prodromal period during which constipation and sleep disorders are common, pathogenic pathways involving oxidative stress, inflammation, and damage to membrane systems such as mitochondria and lysosomes, and collections of aggregated a-synuclein in Lewy bodies and neurites [1]. The gene discussed is SNCA; the disease is Parkinson disease.