The chromosomal complement in persons with Klinefelter’s syndrome is :
**Core Concept**
Klinefelter's syndrome is a genetic disorder characterized by the presence of an extra X chromosome in males, leading to various physical and developmental abnormalities. This condition results from a sex chromosome aneuploidy, where the typical XY sex chromosome configuration is disrupted.
**Why the Correct Answer is Right**
The correct chromosomal complement in individuals with Klinefelter's syndrome is **XXY**. This occurs when a male receives an extra X chromosome from one parent during meiosis, resulting in a 47,XXY karyotype. The extra X chromosome leads to an imbalance in sex hormone production, which can cause developmental delays, infertility, and other characteristic features of the syndrome. The XXY configuration disrupts the normal ratio of X-linked genes to autosomal genes, leading to the characteristic features of Klinefelter's syndrome.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not represent the chromosomal complement associated with Klinefelter's syndrome.
**Option B:** This option is incorrect as it represents the typical chromosomal complement of a female, not a male with Klinefelter's syndrome.
**Option C:** This option is incorrect as it does not accurately represent the chromosomal complement associated with Klinefelter's syndrome.
**Clinical Pearl / High-Yield Fact**
Klinefelter's syndrome is the most common sex chromosome disorder in males, affecting approximately 1 in 650 births. Individuals with Klinefelter's syndrome often present with tall stature, gynecomastia, and infertility due to the imbalance of sex hormones.
**Correct Answer:** C. 47,XXY.