Turner syndrome, a condition that is present at birth and only affects females, is caused by the complete or partial absence of one of the two X chromosomes. This condition generally causes an array of features and symptoms, including short stature, infertility, and heart defects. Because the syndrome is a problem with the chromosomes, there is no cure for this condition, and treatments focus on controlling the features and symptoms of the disorder.
Turner syndrome is a condition that is present at birth and only affects females. The cause of this syndrome is the complete or partial absence of one of the two X chromosomes. This condition can cause a broad array of features and symptoms, from minor cosmetic issues to major heart defects. The amount of features and symptoms is different for each woman. Almost all women with this syndrome have short stature and loss of ovarian function.
Turner syndrome occurs in about 1 in 2,500 female births worldwide, but is much more common among pregnancies that do not survive to term (miscarriages and stillbirths). Prenatal testing has probably decreased the number of diagnosed cases of Turner syndrome.
The cause of this syndrome is the complete or partial absence of one of the two X chromosomes (sex chromosomes).
About half of the individuals with Turner syndrome have monosomy X, which means each cell in the individual's body has only one copy of the X chromosome instead of the usual two sex chromosomes (see X Chromosome Monosomy).
Turner syndrome can also occur if one of the sex chromosomes is partially missing or rearranged, rather than completely missing (see Turner Syndrome and X Chromosome Defects).
Some women with this syndrome have a chromosomal change in only some of their cells, which is known as X chromosome mosaicism (see Mosaic Turner Syndrome).
(Click Cause of Turner Syndrome for more information.)