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Genetics Home Reference: your guide to understanding genetic conditions     A service of the U.S. National Library of Medicine®


Reviewed April 2009

What is retinoblastoma?

Retinoblastoma is a rare type of eye cancer that usually develops in early childhood, typically before the age of 5. This form of cancer develops in the retina, which is the specialized light-sensitive tissue at the back of the eye that detects light and color.

In most children with retinoblastoma, the disease affects only one eye. However, one out of three children with retinoblastoma develops cancer in both eyes. The most common first sign of retinoblastoma is a visible whiteness in the pupil called "cat's eye reflex" or leukocoria. This unusual whiteness is particularly noticeable in photographs taken with a flash. Other signs and symptoms of retinoblastoma include crossed eyes or eyes that do not point in the same direction (strabismus); persistent eye pain, redness, or irritation; and blindness or poor vision in the affected eye(s).

Retinoblastoma is often curable when it is diagnosed early. However, if it is not treated promptly, this cancer can spread beyond the eye to other parts of the body. This advanced form of retinoblastoma can be life-threatening.

When retinoblastoma is associated with a gene mutation that occurs in all of the body's cells, it is known as germinal retinoblastoma. People with this form of retinoblastoma also have an increased risk of developing several other cancers outside the eye. Specifically, they are more likely to develop a cancer of the pineal gland in the brain (pinealoma), a type of bone cancer known as osteosarcoma, cancers of soft tissues such as muscle, and an aggressive form of skin cancer called melanoma.

How common is retinoblastoma?

Retinoblastoma is diagnosed in 250 to 350 children per year in the United States. It accounts for about 4 percent of all cancers in children younger than 15 years.

What are the genetic changes related to retinoblastoma?

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. Most mutations in the RB1 gene prevent it from making any functional protein, so it is unable to regulate cell division effectively. As a result, certain cells in the retina can divide uncontrollably to form cancerous tumors. Some studies suggest that additional genetic changes can influence the development of retinoblastoma; these changes may help explain variations in the development and growth of tumors in different people.

A small percentage of retinoblastomas are caused by deletions in the region of chromosome 13 that contains the RB1 gene. Because these chromosomal changes involve several genes in addition to RB1, affected children usually also have intellectual disability, slow growth, and distinctive facial features (such as prominent eyebrows, a short nose with a broad nasal bridge, and ear abnormalities).

Related Chromosome(s)

Changes involving this chromosome are associated with retinoblastoma.

  • chromosome 13

Related Gene(s)

Changes in this gene are associated with retinoblastoma.

  • RB1

Can retinoblastoma be inherited?

Researchers estimate that 40 percent of all retinoblastomas are germinal, which means that RB1 mutations occur in all of the body's cells, including reproductive cells (sperm or eggs). People with germinal retinoblastoma may have a family history of the disease, and they are at risk of passing on the mutated RB1 gene to the next generation. The other 60 percent of retinoblastomas are non-germinal, which means that RB1 mutations occur only in the eye and cannot be passed to the next generation.

In germinal retinoblastoma, mutations in the RB1 gene appear to be inherited in an autosomal dominant pattern. Autosomal dominant inheritance suggests that one copy of the altered gene in each cell is sufficient to increase cancer risk. A person with germinal retinoblastoma may inherit an altered copy of the gene from one parent, or the altered gene may be the result of a new mutation that occurs in an egg or sperm cell or just after fertilization. For retinoblastoma to develop, a mutation involving the other copy of the RB1 gene must occur in retinal cells during the person's lifetime. This second mutation usually occurs in childhood, typically leading to the development of retinoblastoma in both eyes.

In the non-germinal form of retinoblastoma, typically only one eye is affected and there is no family history of the disease. Affected individuals are born with two normal copies of the RB1 gene. Then, usually in early childhood, both copies of the RB1 gene in retinal cells acquire mutations or are lost. People with non-germinal retinoblastoma are not at risk of passing these RB1 mutations to their children. However, without genetic testing it can be difficult to tell whether a person with retinoblastoma in one eye has the germinal or the non-germinal form of the disease.

Where can I find information about diagnosis or management of retinoblastoma?

These resources address the diagnosis or management of retinoblastoma and may include treatment providers.

  • Gene Review: Retinoblastoma (
  • Genetic Testing Registry: Retinoblastoma (
  • MedlinePlus Encyclopedia: Retinoblastoma (
  • National Cancer Institute: Genetic Testing for Hereditary Cancer Syndromes (

You might also find information on the diagnosis or management of retinoblastoma in Educational resources and Patient support.

General information about the diagnosis ( and management ( of genetic conditions is available in the Handbook. Read more about genetic testing (, particularly the difference between clinical tests and research tests (

To locate a healthcare provider, see How can I find a genetics professional in my area? ( in the Handbook.

Where can I find additional information about retinoblastoma?

You may find the following resources about retinoblastoma helpful. These materials are written for the general public.

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

What other names do people use for retinoblastoma?

  • Glioma, retinal
  • RB

For more information about naming genetic conditions, see the Genetics Home Reference Condition Naming Guidelines ( and How are genetic conditions and genes named? ( in the Handbook.

What if I still have specific questions about retinoblastoma?

Ask the Genetic and Rare Diseases Information Center (

What glossary definitions help with understanding retinoblastoma?

autosomal ; autosomal dominant ; bilateral ; cancer ; cell ; cell division ; chromosome ; disability ; egg ; family history ; gene ; genetic testing ; glioma ; inherit ; inheritance ; inherited ; melanoma ; mutation ; new mutation ; osteosarcoma ; pineal ; pineal gland ; pinealoma ; protein ; pupil ; reflex ; reproductive cells ; retina ; sign ; sperm ; strabismus ; tissue ; tumor ; tumor suppressor gene ; unilateral

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


  • Abramson DH, Schefler AC. Update on retinoblastoma. Retina. 2004 Dec;24(6):828-48. Review. (
  • Antoneli CB, Ribeiro Kde C, Sakamoto LH, Chojniak MM, Novaes PE, Arias VE. Trilateral retinoblastoma. Pediatr Blood Cancer. 2007 Mar;48(3):306-10. Review. (
  • Baud O, Cormier-Daire V, Lyonnet S, Desjardins L, Turleau C, Doz F. Dysmorphic phenotype and neurological impairment in 22 retinoblastoma patients with constitutional cytogenetic 13q deletion. Clin Genet. 1999 Jun;55(6):478-82. (
  • Corson TW, Gallie BL. One hit, two hits, three hits, more? Genomic changes in the development of retinoblastoma. Genes Chromosomes Cancer. 2007 Jul;46(7):617-34. Review. (
  • De Falco G, Giordano A. pRb2/p130: a new candidate for retinoblastoma tumor formation. Oncogene. 2006 Aug 28;25(38):5333-40. Review. (
  • Gene Review: Retinoblastoma (
  • Lohmann DR, Gallie BL. Retinoblastoma: revisiting the model prototype of inherited cancer. Am J Med Genet C Semin Med Genet. 2004 Aug 15;129C(1):23-8. Review. (
  • Madhavan J, Ganesh A, Kumaramanickavel G. Retinoblastoma: from disease to discovery. Ophthalmic Res. 2008;40(5):221-6. doi: 10.1159/000128578. Epub 2008 Apr 29. Review. (
  • Poulaki V, Mukai S. Retinoblastoma: genetics and pathology. Int Ophthalmol Clin. 2009 Winter;49(1):155-64. doi: 10.1097/IIO.0b013e3181924bc2. Review. (
  • Schefler AC, Abramson DH. Retinoblastoma: what is new in 2007-2008. Curr Opin Ophthalmol. 2008 Nov;19(6):526-34. doi: 10.1097/ICU.0b013e328312975b. Review. (
  • Sippel KC, Fraioli RE, Smith GD, Schalkoff ME, Sutherland J, Gallie BL, Dryja TP. Frequency of somatic and germ-line mosaicism in retinoblastoma: implications for genetic counseling. Am J Hum Genet. 1998 Mar;62(3):610-9. (


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? ( in the Handbook.

Reviewed: April 2009
Published: February 1, 2016