This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Genetics, Subject name: Biochemistry
Retinoblastoma can result from a mutation in: 
Select and explain. 
A. Ras proto-oncogene, B. ErbB proto-oncogene, C. p 53 gene, D. RB 1 gene
D: RB 1 gene
Answer: D: RB 1 gene 
Explanation: Ans. D. RB 1 geneRetinoblastoma is a cancer common in children below 15 years of age. Itis caused by abnormalities of a gene called RB1, which is located on a region of the long (q) arm of chromosome 13 designated 13q14. Although most retinoblastomas are caused by mutations within the RB1 gene, a small percentage of retinoblastomas result from a deletion of the 13q14 region.