This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetic Basics Of Carcinogenesis, Subject name: Pathology
All of the following statements are true regarding retinoblastoma, except: 
Select and explain. 
A. Rb genes play major role in cell cycle regulation, B. Require deletion of both the Rb genes, C. Familial variant is autosomal dominant in inheritance, D. Rb gene is on chromosome 14p13
D: Rb gene is on chromosome 14p13
Answer: D: Rb gene is on chromosome 14p13 
Explanation: Rb gene Governor of the cell cycle Negative regulator of the G1/S cell cycle transition. Located on 13q14 chromosome. To explain the two patterns of occurrence of retinoblastoma, Knudson proposed "two hit" hypothesis of oncogenesis. Two mutations (hits), involving both alleles of RB at chromosome locus 13q14, are required to produce retinoblastoma. Familial variant is autosomal dominant in inheritance.