Gynaecomastia is common feature seen in

Options

A. Down's syndrome
B. Turner's syndrome
C. cystic fibrosis
D. Klinefelter's syndrome

Answer

**Step-by-Step Solution:**

1. **Understanding Gynecomastia**: Gynecomastia is defined as the enlargement or development of breast tissue in males. It is a condition that can occur due to various hormonal imbalances.

2. **Identifying the Options**: The question provides three options: Down syndrome, cystic fibrosis, and Klinefelter's syndrome. We need to determine which of these conditions is commonly associated with gynecomastia.

3. **Analyzing Down Syndrome**: Down syndrome is a genetic disorder caused by the presence of an extra chromosome 21. While individuals with Down syndrome may have various physical features, gynecomastia is not a common characteristic associated with this condition.

4. **Analyzing Cystic Fibrosis**: Cystic fibrosis is a genetic disorder that primarily affects the lungs and digestive system. It is caused by mutations in the CFTR gene. Gynecomastia is not a typical feature of cystic fibrosis.

5. **Analyzing Klinefelter's Syndrome**: Klinefelter's syndrome is a genetic condition that occurs in males who have an extra X chromosome, resulting in a chromosomal pattern of XXY. This condition is associated with various symptoms, including infertility, small testicular size, and the development of breast tissue (gynecomastia).

6. **Conclusion**: Based on the analysis, Klinefelter's syndrome is the condition that is most commonly associated with gynecomastia. Therefore, the correct answer is Klinefelter's syndrome.

**Final Answer**: Klinefelter's syndrome is the common feature associated with gynecomastia.

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