Turner's syndrome was first diagnosed in 1938 by American physician Henry Hubert Turner (1892–1970). It is also known as Ullrich-Turner syndrome or Bonnevie-Ulrich-Turner syndrome and may also be referred to as gonadal dysgenesis. The syndrome is a rare genetic disorder that affects approximately one in 2,000 to 5,000 females. Its cause is not known; what is understood is that it is characterized by chromosomal abnormalities that result in underdeveloped sexual characteristics. Ordinarily, females have two X chromosomes and males have an X and Y chromosome. The Y chromosome is required for the development of testicles in males. In the female, both X chromosomes are needed for normal ovarian development, and when sex cells divide, an equal amount of genetic material is divided into each. In cases of Turner's syndrome, genetic material is missing from one of the female chromosomes.
Turner's syndrome is usually diagnosed at birth or adolescence, at the time when the girl would otherwise have gone through puberty – if there are no symptoms it can remain undetected until then. If it is suspected at birth, a special blood test called a karyotype is used. This counts the number of chromosomes present and is able to identify any abnormal or missing pieces. There are a number of health problems associated with gonadal dysgenesis, from major heart defects to minor defects in tissue development. These effects can vary and depend on how the cells within the body are affected by the changes to the X chromosome. The majority of girls with Turner's syndrome are infertile, due to their incomplete reproductive organs — because it prevents the ovaries from developing properly, it affects sexual development. The ovaries are responsible for creating the hormones that control breast growth and menstruation, hence girls will not experience these changes associated with puberty, although treatments are available. Coping with the syndrome may cause secondary psychological issues, such as low self-esteem and issues with body image and femininity.
Research into the possible psychiatric implications of Turner's syndrome is still in its infancy. There is some evidence to suggest living with the condition correlates with a vulnerability to psychiatric syndromes, however this may well be linked to external factors such as public attitudes towards the physical appearance of sufferers, and as such any anxiety or depression experienced may not be directly related to the condition itself. Girls with Turner's may have fewer romantic attachments and sexual experience than girls of a comparable age but again, this could also have an explanation unrelated to the syndrome. Some studies have shown significantly lower occupational and academic achievement in affected girls; however studies into the subject are not yet developed sufficiently to offer a full picture, and there have been conflicting results from various researchers.
Another common effect is a shortness of stature — the average height of girls with this condition is 4 feet 7 inches, or 1.4 meters. The condition can also be accompanied by learning difficulties; webbed neck and low posterior hair line; heart and kidney abnormalities; obesity; formation of keloids (thick scars); hypothyroidism and lymphedema (swelling due to an obstruction or deficiency of the lymphatic drainage system). Other manifestations include upturned nails, drooping eyelids, a small lower jaw, loss of hearing, pigmented moles, a broad chest and abnormally low positioning of the ears. Despite girls with the condition generally having normal intelligence, learning difficulties may include problems with spatial perception, visual-motor coordination and math. Females with the syndrome may also be socially immature for their age, however they are generally able to attend regular school and can write well, develop good language skills and memorize information as well as others.
There is no cure for Turner's syndrome as it is caused by chromosomal abnormality, however there are treatments that can relieve some of the problems associated with it. Hormonal intervention, usually started around the age of 15, can help maintain sexual development (girls may undergo partial breast development and menstruate spontaneously, but this will usually cease). Hormone therapy maintains this development and prevents osteoporosis (bone degradation) in later life. If growth hormone treatment is started early enough, a girl may reach a height within the average range. Some women may be able to become pregnant through in vitro fertilization.