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.
In children with the heritable genetic form of retinoblastoma there is a mutation on chromosome 13, called the RB1 gene. The genetic codes found in chromosomes control the way in which cells grow and develop within the body.If a portion of the code is missing or altered (mutation) a cancer may develop.or the protein, see Retinoblastoma protein. Retinoblastoma (Rb) is a rare form of cancer that rapidly develops from the immature cells of a retina, the light-detecting tissue of the eye. It is the most common malignant cancer of the eye in children, and it is almost always found in young children.