Gan Marta was a Bajoran female who, together with her husband Gan Treo, served as a foster parent to Orta.

Marta and Treo collaborated with the Cardassians who were occupying Bajor at the time. When Orta was ten (circa 2348), both foster parents were executed by the Cardassians for providing aid to Bajoran refugees. Their treatment of Orta while he was a child caused him to hate them for the rest of his life. (DS9 - The Brave and the Bold, Book One novella: The Second Artifact)