E cadherin gene deficiency is seen in
**Core Concept**
E-cadherin is a transmembrane glycoprotein that plays a crucial role in cell-cell adhesion, particularly in epithelial tissues. Defects in the E-cadherin gene (CDH1) can lead to loss of cell adhesion, contributing to various pathological conditions.
**Why the Correct Answer is Right**
E-cadherin gene deficiency is associated with an increased risk of developing hereditary diffuse gastric cancer and lobular breast cancer. The CDH1 gene encodes the E-cadherin protein, which mediates cell-cell adhesion through homophilic interactions. Mutations in the CDH1 gene disrupt this interaction, leading to loss of cell adhesion and increased cancer susceptibility. In gastric cancer, E-cadherin deficiency is thought to contribute to the diffuse type of gastric cancer, characterized by a loss of glandular architecture and a high degree of cellular disorganization.
**Why Each Wrong Option is Incorrect**
* **Option A:** E-cadherin deficiency is not primarily associated with skin disorders like psoriasis or eczema.
* **Option B:** While E-cadherin is involved in cell-cell adhesion, its deficiency is not directly linked to neurodegenerative diseases like Alzheimer's or Parkinson's.
* **Option C:** E-cadherin deficiency is not a hallmark of cardiovascular diseases like atherosclerosis or hypertension.
**Clinical Pearl / High-Yield Fact**
The CDH1 gene mutation is inherited in an autosomal dominant pattern, meaning a single copy of the mutated gene is sufficient to increase cancer risk. This highlights the importance of genetic counseling and screening for individuals with a family history of hereditary diffuse gastric cancer.
**Correct Answer: C. Hereditary diffuse gastric cancer.**