Retinoblastoma is a rare type of cancer that affects the eyes, typically only in children. The primary cause of retinoblastoma is a mutation in the RB1 gene, located on chromosome 13. This gene is responsible for controlling the growth of cells in the retina, and when mutated, it can cause those cells to become cancerous.
The reason why retinoblastoma only occurs in children is because they are more likely to have the mutated RB1 gene. This gene is typically passed from parent to child, and due to a lack of genetic diversity, it is much more common for children to inherit the mutated gene than adults. In addition, since children are still growing and developing, their cells are more prone to mutation, which can further increase their chances of developing retinoblastoma.
In addition to the genetic factors, environmental factors can also play a role in retinoblastoma. Exposure to certain toxins, radiation, or other environmental factors can increase the risk of developing the disease. In some cases, parents who have been exposed to these environmental factors may pass them on to their children, leading to an increased risk of retinoblastoma.
Overall, retinoblastoma is a rare disease, but it is more likely to occur in children due to their increased likelihood of inheriting the mutated RB1 gene, as well as their higher risk of environmental factors leading to the development of the disease.