Turner syndrome (TS) is a chromosomal condition that describes girls and women with common features, physical traits and medical conditions that are caused by the complete or partial absence of one X chromosome.
Typically, females have 46 chromosomes which include two X chromosomes, while males have one X and one Y chromosome.
It is estimated that TS occurs in approximately one in 2,000 live female births.
Girls who are missing one complete X chromosome have what is called monosomy X, often referred to as 'classic TS'.
Others are missing only a part of the second X chromosome, or have some structural rearrangements of the chromosome.
Girls who have a missing or rearranged chromosome in some but not all cells of the body have a mosaic karyotype.
