Mark the odd one wrt chromosomal disorder

Options

A. Down syndrome
B. klinefelters syndrome
C. Turner syndrome
D. phenylketonuria

Answer

**Step-by-Step Solution:**

1. **Identify the Options:**
The options given are:
- Down's syndrome
- Klinefelter's syndrome
- Turner's syndrome
- Phenylketonuria

2. **Classify the Disorders:**
- Down's syndrome, Klinefelter's syndrome, and Turner's syndrome are all chromosomal disorders. They arise from abnormalities in chromosome number or structure.
- Phenylketonuria (PKU), on the other hand, is a genetic disorder caused by a mutation in a single gene that affects metabolism, specifically the enzyme phenylalanine hydroxylase.

3. **Determine the Odd One Out:**
Since Down's syndrome, Klinefelter's syndrome, and Turner's syndrome are chromosomal disorders, while Phenylketonuria is a genetic disorder, the odd one out is Phenylketonuria.

4. **Conclusion:**
Therefore, the correct answer to the question "Mark the odd one with respect to chromosomal disorder" is Phenylketonuria (Option 4).

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