Hereditary retinoblastomas develop from the following chromosomal deletion?
**Core Concept**
Hereditary retinoblastoma is a type of cancer that affects the retina, primarily in young children. It is associated with a genetic mutation in a specific tumor suppressor gene. This mutation leads to uncontrolled cell growth and tumor formation.
**Why the Correct Answer is Right**
The correct answer is related to the RB1 gene, which is a tumor suppressor gene located on chromosome 13q14. The RB1 gene plays a crucial role in regulating the cell cycle, preventing excessive cell division, and promoting apoptosis. In individuals with hereditary retinoblastoma, a deletion or mutation in the RB1 gene leads to the loss of its tumor suppressor function, resulting in the development of retinoblastoma.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as it does not correspond to a known chromosomal deletion associated with hereditary retinoblastoma.
* **Option B:** This option is incorrect as it refers to a different type of cancer, not retinoblastoma, and is associated with a different genetic mutation.
* **Option C:** This option is incorrect as it does not accurately represent the chromosomal deletion associated with hereditary retinoblastoma.
**Clinical Pearl / High-Yield Fact**
Hereditary retinoblastoma often presents bilaterally, with multiple tumors in each eye, and is associated with a higher risk of developing secondary cancers, such as osteosarcoma and melanoma.
**Correct Answer:** C. 13q14 deletion of the RB1 gene.