Prader villi syndrome is an example of?
**Core Concept**
Prader-Willi syndrome is a rare genetic disorder characterized by short stature, intellectual disability, and excessive appetite leading to obesity. It is caused by the deletion or inactivation of genes on chromosome 15 inherited from the father.
**Why the Correct Answer is Right**
Prader-Willi syndrome is an example of genomic imprinting, where the expression of a gene depends on its parental origin. The deletion of genes on chromosome 15 inherited from the father leads to the silencing of the paternal copy, resulting in the loss of function of the gene. This is a classic example of an imprinting disorder, where the expression of a gene is determined by its parental origin rather than its genetic content.
**Why Each Wrong Option is Incorrect**
* **Option A:** Prader-Willi syndrome is not an example of a chromosomal translocation, which is a type of genetic rearrangement where a segment of DNA breaks off from one chromosome and attaches to another.
* **Option B:** Prader-Willi syndrome is not an example of a mitochondrial disorder, which is a type of genetic disorder caused by mutations in the mitochondrial DNA.
* **Option C:** Prader-Willi syndrome is not an example of a multifactorial disorder, which is a type of genetic disorder caused by the interaction of multiple genetic and environmental factors.
**Clinical Pearl / High-Yield Fact**
Prader-Willi syndrome is often associated with hypogonadism, which can lead to infertility and delayed puberty. Patients with Prader-Willi syndrome also have an increased risk of developing obesity-related complications, such as type 2 diabetes and cardiovascular disease.
**Correct Answer: D. Genomic imprinting.**