PATL2 and major depressive disorder: Given that prodromal PD is hallmarked by nonmotor symptoms, and that many of the nonmotor symptoms (e.g., olfactory dysfunction, constipation, and depression) in the prodromal PD diagnostic criteria were more prevalent in women than men61,62, we additionally hypothesize that PATL2 is also involved in the mechanisms underlying the development of nonmotor symptoms.