Which genetic condition is characterized by a karyotype of XXY?

Klinefelter syndrome is characterized by the presence of an extra X chromosome in males, resulting in a karyotype of XXY. This genetic condition often leads to various physical and developmental characteristics, including reduced testosterone levels, decreased fertility, and potential learning difficulties. The extra X chromosome is a result of nondisjunction during meiosis, affecting male sexual development.

The aspects of Klinefelter syndrome can include gynecomastia (breast tissue development), taller stature, and less muscular build compared to XY males. Individuals may also exhibit features like delayed speech and language development.

In contrast, Turner syndrome occurs in females with a karyotype of X0, Down syndrome can be identified by trisomy 21, and Triple X syndrome results in an extra X chromosome in females (XXX). Each of these conditions has distinct genetic and phenotypic characteristics that differentiate them from Klinefelter syndrome.