What is the karyotype of Turner syndrome?

The karyotype associated with Turner syndrome is characterized by the presence of a single X chromosome and the absence of a second sex chromosome, resulting in the karyotype 45, X0. Turner syndrome occurs in females and is one of the most common chromosomal abnormalities, affecting roughly 1 in 2,500 live female births.

Individuals with Turner syndrome typically present with various physical features and health issues such as short stature, webbing of the neck, and primary amenorrhea due to ovarian dysgenesis. The absence of a second sex chromosome (the "0" in 45, X0) is critical in this syndrome, as it leads to the clinical manifestations observed.

In the context of the other karyotype options, 46, XX represents a normal female; 47, XXY denotes Klinefelter syndrome, a male chromosomal condition characterized by the presence of an extra X chromosome; and 46, XY indicates a normal male karyotype. None of these represent the chromosomal configuration typical of Turner syndrome.