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
Differential expression of same gene depending on parent of origin is referred to as: 
Select and explain. 
A. Genomic imprinting, B. Mosaicism, C. Anticipation, D. Non penetrance
A: Genomic imprinting
Answer: A: Genomic imprinting 
Explanation: Ans. A. Genomic Imprinting(Ref: Robbins 9/e page 172)Studies over the past two decades have provided definite evidence that, at least with respect to some genes, important functional differences exist between the paternal allele and the maternal allele. These differences result from an epigenetic process called imprinting.