Preferential expression of the gene depending upon the parent of origin is called:
**Core Concept**
The preferential expression of a gene based on its parental origin is a phenomenon where the gene is expressed more from the allele inherited from one parent over the other. This is often seen in imprinted genes, where the expression is determined by the parent of origin due to epigenetic modifications.
**Why the Correct Answer is Right**
Genomic imprinting is a process where a gene is expressed based on its parental origin. This is mediated by epigenetic marks such as DNA methylation and histone modifications. In some cases, the expression of a gene is suppressed in one parent and active in the other, leading to a preferential expression of the gene. For instance, the insulin-like growth factor 2 (IGF2) gene is imprinted, meaning it is expressed only from the paternal allele, while the insulin-like growth factor 2 receptor (IGF2R) gene is imprinted, meaning it is expressed only from the maternal allele.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the concept of preferential gene expression based on parental origin.
* **Option B:** While this option may sound similar, it is not directly related to the concept of genomic imprinting.
* **Option D:** This option is not a recognized term in the context of gene expression and parental origin.
**Clinical Pearl / High-Yield Fact**
Genomic imprinting is a crucial mechanism in developmental biology and disease. Aberrant imprinting has been implicated in various diseases, including cancer, neurological disorders, and growth abnormalities. Understanding genomic imprinting is essential for developing targeted therapies for these conditions.
**Correct Answer: C. Genomic imprinting.**