**Question:** The peripheral blood smear of a patient shows features of thalassemia, also presented with anaemia. Family history is also +ve. The investigation done to establish the diagnosis is -

A. Hb electrophoresis
B. Complete blood count (CBC)
C. Mutation analysis
D. Hemoglobin level

**Correct Answer:** A. Hb electrophoresis

**Core Concept:** Thalassemia is a group of inherited blood disorders characterized by reduced or absent production of hemoglobin. Two main types are major and minor, which are caused by mutations in the beta-globin gene. The diagnosis of thalassemia involves identification of specific hemoglobin variants through electrophoresis and genetic testing.

**Why the Correct Answer is Right:** Hb electrophoresis is the appropriate test to diagnose thalassemia as it separates and identifies different hemoglobin variants present in the patient's blood. This test is essential in determining the type of thalassemia and providing valuable information for treatment and counseling purposes.

**Why Each Wrong Option is Incorrect:**

1. CBC (B) provides general hemogram parameters, but it does not specifically identify the type of hemoglobin variants present in thalassemia.
2. D. Hemoglobin level (D) is a basic lab parameter, but it does not provide detailed information about the hemoglobin variants present in the patient's blood.
3. Mutation analysis (C) is an essential tool in genetic counseling but not specific to diagnosing thalassemia; it is used for genetic counseling and carrier detection rather than the specific diagnosis of thalassemia.

**Clinical Pearl:** Family history plays a crucial role in suspecting thalassemia, but the definitive diagnosis requires laboratory tests, particularly Hb electrophoresis. Early diagnosis is vital for proper management and to provide genetic counseling for affected family members.