A descendent gene is a gene that is passed down from one generation to the next. The term 'descendent gene' is often used in genetics and genealogy to refer to a gene that is inherited from an ancestor. In crosswords, the terms 'SCION' (5 letters) and 'sansei' (6 letters) are often used as synonyms for 'descendent gene'. SCION is derived from the Latin word for 'DESCENDANT', while sansei is a Japanese term meaning 'third generation'.