RB1

The RB1 gene belongs to a class of genes known as tumor suppressors. Like other tumor suppressor genes, RB1 regulates the cycle of cell division by keeping cells from growing and dividing too rapidly or in an uncontrolled way. The protein product of RB1 is located in the nucleus of cells throughout the body. This protein stops certain other proteins from triggering the process by which DNA makes a copy of itself (DNA replication). The protein may also play a role in the determination of cell type (differentiation) and programmed cell death (apoptosis).

retinoblastoma - increased risk from variations of the RB1 gene

More than 200 different disease-causing mutations have been reported in the RB1 gene. A rearrangement or deletion of the part of chromosome 13 that contains RB1 is also possible. Most of these mutations prevent the RB1 gene from producing any functional protein. Without this protein, cells are unable to effectively regulate cell division and may grow and divide uncontrollably to form a tumor. It is not known why RB1 mutations most often lead to retinoblastoma (a tumor of the retina of the eye) instead of cancers in other parts of the body.

bladder cancer - associated with the RB1 gene

Noninherited mutations that inactivate the RB1 gene have been reported in some cases of bladder cancer. Mutations in RB1 are thought to be important in the development of this type of cancer, and can help predict whether some cancers will grow and invade more rapidly than others.

other cancers - increased risk from variations of the RB1 gene

In addition to retinoblastoma and bladder cancer, RB1 has been shown to be involved in other types of cancer. RB1 mutations increase the risk of developing pinealoma (a cancer of the pineal gland in the brain) and osteosarcoma (a type of bone cancer) in people with retinoblastoma. Changes in this gene have also been seen in some cases of lung cancer and melanoma, which is a form of skin cancer.

13q14.2

The RB1 gene is located on the long (q) arm of chromosome 13 at position 14.2.

See How do geneticists indicate the location of a gene? in the Handbook.

You and your healthcare professional may find the following resources about RB1 helpful.

• Educational resources - Information pages
  Genes and Disease
• ClinicalTrials.gov - Linking patients to medical research
• Gene Reviews - Clinical summary
• Gene Tests - DNA tests ordered by healthcare professionals

You may also be interested in these resources, which are designed for genetics professionals and researchers.

• PubMed - Recent literature
• OMIM - Genetic disorder catalog
• Research Resources - Tools for researchers (4 links)

See How are genetic conditions and genes named? in the Handbook.

The Handbook provides basic information about genetics in clear language.

• What is DNA?
• What is a gene?
• How does a gene make a protein?
• How can gene mutations cause disorders?

These links provide additional genetics resources that may be useful.

• Genetics education
• Human Genome Project
• Resources for Genetic Researchers

apoptosis ; cancer ; cell division ; chromosome ; deletion ; differentiation ; disease-causing mutation ; DNA ; DNA replication ; gene ; mutation ; nucleus ; osteosarcoma ; protein ; rearrangement ; retina ; tumor ; tumor suppressor gene

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.