Retinoblastoma causes

Overview
Retinoblastoma is a cancer of the retina. Development of this tumor is initiated by mutations that inactivate both copies of the RB1 gene, which codes for the retinoblastoma protein.

Causes
Retinoblastoma is caused by a mutation in a gene controlling cell division, causing cells to grow out of control and become cancerous.

In a little over half of the cases, this mutation develops in a child whose family has never had eye cancer.

Other times the mutation is present in several family members. If the mutation runs in the family, there is a 50% chance that an affected person's children will also have the mutation. They will therefore have a high risk of developing retinoblastoma themselves.

The cancer generally affects children under the age of 6. It is most commonly diagnosed in children aged 1 - 2 years.