Essay On Retinoblastoma

Retinoblastoma is an eye cancer that starts in the retina, the sensitive lining on the inside of an eye. The disease most commonly affects young children, but can occasionally occur in older adults. Retinoblastoma may occur in either one or both eyes. The retina is made up of nerve tissue that senses light as it comes through the front of the eyes. Then the retina sends signals through the optic nerve to the brain, where these signals are intercepted as images. The symptoms of retinoblastoma include swelling and redness in the eyes, eyes that appear to be looking in different directions, and a white or pale pink color in the pupil of the eye when light is shone on it. Additionally, individuals affected by retinoblastoma often experience vision problems, eye pain, rapid involuntary eye movement, differently colored irises, and enlarged pupils that do not get smaller when when exposed to bright light.
This gene makes a protein, called (pRb), that helps stop certain cells from growing too quickly. In about 1 out of 3 children with retinoblastoma, the abnormality in the RB1 gene is present at the child's birth and is in all the cells, including the retinas of the eyes. This is known as a germline mutation. Children born with a mutation in the RB1 gene usually develop retinoblastoma in both eyes, known as bilateral retinoblastoma, and there are often several tumors within an eye, known as multifocal retinoblastoma. Each cell normally has two RB1 genes, and as long as a retinal cell has at least one RB1 gene that works as it should, it will not form a retinoblastoma. But when both of the RB1 genes are mutated, a cell can grow without proper guidance. This can lead to further gene mutations, which in turn may cause certain cells to become