Which one is sex related disease ?

Options

A. christmas disease
B. Klinefelter 's syndrome
C. Phenylketonuria
D. Albinism

Answer

**Step-by-Step Solution:**

1. **Understanding Sex-Linked Diseases**:
- Sex-linked diseases are inherited through the sex chromosomes, which are the X and Y chromosomes. These diseases are often associated with genes located on these chromosomes.

2. **Analyzing the Options**:
- The question provides four options: Christmas disease, Klinefelter syndrome, phenylketonuria, and albinism. We need to determine which of these is a sex-linked disease.

3. **Evaluating Christmas Disease**:
- Christmas disease, also known as hemophilia B, is a condition where blood does not clot properly due to a deficiency in clotting factor IX. This condition is indeed linked to the X chromosome, making it a sex-linked disease.

4. **Evaluating Klinefelter Syndrome**:
- Klinefelter syndrome occurs in males who have an extra X chromosome (XXY). This condition is directly related to the sex chromosomes and is classified as a sex-linked disease.

5. **Evaluating Phenylketonuria**:
- Phenylketonuria (PKU) is an inherited disorder that results from a deficiency of the enzyme phenylalanine hydroxylase. This condition is caused by a mutation in a gene on chromosome 12, not a sex chromosome, so it is not a sex-linked disease.

6. **Evaluating Albinism**:
- Albinism is a genetic condition characterized by the absence or reduction of melanin pigment. It is caused by mutations in several genes and is not linked to the sex chromosomes, thus it is not a sex-linked disease.

7. **Conclusion**:
- After evaluating all the options, Klinefelter syndrome is identified as a sex-linked disease due to its association with the sex chromosomes (XXY). Therefore, the correct answer is Klinefelter syndrome.

**Final Answer**: Klinefelter syndrome

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