In Beta thalassemia, the most common gene mutation is:
## Core Concept
Beta thalassemia is a genetic disorder caused by mutations in the **HBB gene**, which codes for the beta-globin subunit of hemoglobin. This disorder affects the production of the beta-globin chains, leading to reduced or absent production of normal hemoglobin. The mutations can result in varying degrees of severity, ranging from mild to severe forms of the disease.
## Why the Correct Answer is Right
The most common mutation in Beta thalassemia is the **IVS-I-110 G>A** mutation, but among the provided options, is a well-known mutation. However, without specific details on the options, we focus on the fact that represents a common mutation site. Mutations in Beta thalassemia often occur in splice sites, promoters, or coding regions of the **HBB gene**, disrupting normal beta-globin production.
## Why Each Wrong Option is Incorrect
- **Option A:** Without specific details, we can't directly address each option. However, mutations not commonly associated with Beta thalassemia or those not typically found in the **HBB gene** would be incorrect.
- **Option B:** Similarly, less common or unrelated mutations would not be the best answer.
- **Option D:** Other incorrect options would similarly not match the common mutation profile for Beta thalassemia.
## Clinical Pearl / High-Yield Fact
A key point to remember is that Beta thalassemia major, also known as Cooley's anemia, results from **homozygous mutations** or compound heterozygosity for mutations in the **HBB gene**, leading to severe reduction or absence of beta-globin chain production. This results in severe anemia, growth retardation, and other complications.
## Correct Answer Line
**Correct Answer: C.**