Which of the following is correct match ?

Options

A. Down's syndrome - `21^(st)` chromosome
B. Sickle cell anaemia - X - chromosome
C. Haemophilia - Y-chromosome
D. Parkinson's disease - X & Y chromosome

Answer

To solve the question of which of the following is the correct match regarding genetic disorders and their chromosomal associations, we will analyze each disorder mentioned in the video transcript step by step.

### Step 1: Analyze Down Syndrome
- **Down Syndrome** is characterized by the presence of an extra chromosome at the 21st position, leading to a condition known as **trisomy 21**.
- This condition is indeed a **chromosomal disorder**.

**Conclusion for Step 1**: Down Syndrome is correctly matched with the 21st chromosome.

### Step 2: Analyze Sickle Cell Anemia
- **Sickle Cell Anemia** is a genetic blood disorder caused by a **point mutation** in the hemoglobin gene located on an **autosomal chromosome** (specifically chromosome 11).
- It is not a chromosomal disorder but rather a **single-gene disorder**.

**Conclusion for Step 2**: Sickle Cell Anemia is incorrectly matched with a chromosomal disorder.

### Step 3: Analyze Hemophilia
- **Hemophilia** is a bleeding disorder that is caused by a deficiency in clotting factors, and it is linked to the **X chromosome**.
- It is classified as a **sex-linked disorder** rather than a chromosomal disorder.

**Conclusion for Step 3**: Hemophilia is incorrectly matched with a chromosomal disorder.

### Step 4: Analyze Parkinson's Disease
- **Parkinson's Disease** is a neurodegenerative disorder that results from the loss of brain cells and is not caused by chromosomal abnormalities.
- It is not classified as a chromosomal disorder.

**Conclusion for Step 4**: Parkinson's Disease is incorrectly matched with a chromosomal disorder.

### Final Conclusion
The only correct match from the options provided is **Down Syndrome** with the **21st chromosome**. Therefore, the correct answer is:

**Correct Match**: Down Syndrome - 21st Chromosome

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