Question

A 30 year old male complains of infertility. He appears tall and has gynaecomastia. Genitalia appear normal except for bilateral small testes. His chromosomal pattern is likely to be

• A. 45 XO
• B. 47 XXY
• C. 47 XYY
• D. 46 XY

Hint:

Tall male with gynaecomastia and small testes points to an extra X chromosome.

Answer 1

The Correct Option is B

The question describes a man with infertility, tall height, breast tissue growth (gynaecomastia), and testes that are small on both sides. This picture points to a specific sex chromosome disorder.

1. 45 XO: This is Turner syndrome, which affects females, not males, so it cannot fit this case.
2. 47 XXY: An extra X chromosome in a male causes Klinefelter syndrome. The testes fail to grow properly, testosterone stays low, and estrogen effects give tall stature and breast enlargement, matching every feature here.
3. 47 XYY: Men with this pattern are usually tall but have normal testes, normal fertility, and no gynaecomastia, so it does not match.
4. 46 XY: This is the normal male karyotype and gives no reason for infertility or gynaecomastia.

The findings of small testes, gynaecomastia, tall build and infertility together point only to Klinefelter syndrome, karyotype 47 XXY.

Let's summarize:

• Small firm testes plus gynaecomastia plus infertility in a tall male is the classic Klinefelter picture.
• The extra X chromosome (47 XXY) is behind the low testosterone and impaired sperm production.

So the chromosomal pattern is 47 XXY.