Question

Pick up the statements that are true about Klinefelter syndrome.
A. Feminine sexual development is not completely suppressed
B. Karyotype is 47 XXY.
C. The male is negative for Barr body.
D. Secondary sexual characters are well developed.

Answer 1

Hint:- Klinefelter syndrome is a genetic condition where a male is born with an extra copy of the X chromosome. It is a sex-linked disorder of chromosomes. It affects males and is not diagnosed until the adulthood of the person. When an abnormal egg with XY composition is fertilized by a sperm with a Y chromosome a zygote is formed with XXY composition.

Complete step-by-step solution:-
Feminine sexual development is not completely suppressed since there is an extra X present in the person then the male shows some physical characters that are feminine. In the case of a normal male, there are 46 pairs of the chromosome where 44 pairs make autosomes and one pair is the X chromosome, and one pair of the Y chromosome. But in the case of Klinefelter syndrome, there
are 47 pairs of chromosomes where 44 pairs is autosome and one pair is Y chromosome and two pairs of X chromosomes.

The Barr bodies always present one less than the X chromosome. A normal male has an XY type of chromosome. Hence the Barr body will be zero. But in the case of Klinefelter's syndrome, there are two X chromosomes then the Barr bodies will be one. In the case of normal males, the development of secondary sexual characters starts during the teenage stage. But in the case of Klinefelter's syndrome, there is a decrease in androgen production. Hence there will be a decrease in the secondary sexual characters.

The correct answer for the question is feminine sexual character is not completely depressed and Karyotype is 47XXY. Options A and B are correct.

Note:- Other sex-linked syndromes are:
1. Turners syndrome – it affects females where instead of XX type of chromosome it will be XO.
2. Poly- X Female- the female affected with this condition will have XXX in the place of XX.
3. XYY males – males show the presence of two Y chromosomes than one Y chromosome wit X.