duete; see due, ty 2 ]. syn: duty, obligation refer to something a person feels bound to do. A duty often applies to what a person performs in fulfillment of the permanent dictates of conscience, piety, right, or law: one's duty to tell the truth; a parent's duty to raise children properly.
Mutations in the RB1 gene are responsible for most cases of retinoblastoma. RB1 is a tumor suppressor gene, which means that it normally regulates cell growth and keeps cells from dividing too rapidly or in an uncontrolled way.
Rb Retinoblastoma is an eye tumor of young children that occurs in a hereditaryis an eye tumor of young children that occurs in a hereditary or a sporadic form. Deletions have been found in chromosome 13 associated with retinoblastoma. Inheritance of one defective gene puts the individual at greater risk.