Middlesex by Jeffrey Eugenides
"Middlesex" is the story of a family. From the grandparents' early life in Asia Minor to the sexually misidentified Cal/Callie born in Detroit. The grandparents were siblings who fell in love. After fleeing a war, they moved to Detroit where a cousin lived. Free of the people who knew them, they married. The cousin had secrets of her own and kept theirs.
Because of a genetic defect, Cal/Callie is intersexed and must figure out which sex is the best fit.