Definition of Y chromosome
Y chromosome: The sex chromosome that is found, together with an X chromosome, in most normal males. The Y chromosome contains the unique male-determining gene and the male fitness genes that are active only in the testis and are responsible for the formation of sperm. Other genes on the Y chromosome have counterparts on the X chromosome, are active in many body tissues, and play crucial 'housekeeping' roles with the cell.
Last Editorial Review: 3/19/2012
Back to MedTerms online medical dictionary A-Z List
Need help identifying pills and medications?