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What is Hereditary retinoblastomas develop from the following chromosomal deletion? and explain in detail?
Retinoblastoma (RB) gene has been identified as 14 band on the long-arm of chromosome 13 (13q14) and is a 'cancer suppressor' or 'antioncogenic' gene.Deletion or inactivation of this protective gene by two mutations (Knudson's two-hit hypothesis) results in the occurrence of retinoblastoma.Ref: Khurana; Comprehensive ophthalmology; 4th edition; Page no: 280