Question

4.A child is born with a single functional allele of a tumor suppressor gene. At the age of five the remaining normal allele is lost through a point mutation. As a result, the ability to inhibit cell cycle progression until the cell is ready to divide is lost. Which of the following neoplasms is most likely to arise via this mechanism?
A Breast ductal carcinoma
B Pulmonary small cell anaplastic carcinoma
c Ocular retinoblastoma
D Cerebral astrocytoma
E Chronic myeloid leukemia

Answer 1

As the child is born with a single functional allele of a tumor suppressor gene, the condition is genetic defect which in hereditary. The other allele is lost through mutation.
The neoplasm is developed in childhood.
Retinoblastoma is a rare neoplastic condition in young children that develops from absent functional gene at birth or mutation during childhood. This makes the retinoblastoma protein dysfunctional resulting in uncontrolled growth of retinal cells. It may cause vision loss.
So the answer is (c) ocular retino