Mo. Rev. Stat. § 474.310: Who may make will.

Any person of sound mind, eighteen years of age or older or any minor emancipated by adjudication, marriage or entry into active military duty into the military may by last will devise his or her real or personal property and may also devise the whole or any part of his or her body to any college, university, licensed hospital or to the state anatomical board for use in the manner expressly provided by his or her will or otherwise.