What is Monosomy X (Turner syndrome)?

Monosomy X, also known as Turner syndrome, is a condition that causes short stature, abnormal puberty, birth defects, and infertility in affected females. It is caused by a difference in the number of sex chromosomes. Females typically have two X chromosomes, while males typically have one X and one Y chromosome. Turner syndrome occurs when a female has only one complete and functioning copy of the X chromosome in the cells of the body instead of two. The symptoms seen in Turner syndrome are a result of this missing material impacting the growth and development of an affected individual.

Common features of Turner syndrome include short stature, puberty that is absent or delayed, infertility, heart and kidney abnormalities, hearing loss, eye and skeletal abnormalities, and thyroid disease. Individuals may have unique physical characteristics such as distinct facial features and a wide and short neck. Most people with Turner syndrome have normal intelligence, though they may experience difficulties in certain areas such as math, memory, attention, or social skills.

How common is Turner Syndrome?

The incidence of Turner syndrome in the population is 1 in 2,500 live births.

How is Turner Syndrome treated?

There is no cure for Turner syndrome. Treatment for the condition is directed at managing the specific symptoms an individual has. Common interventions include medications to help achieve puberty at an appropriate age and increase adult height. Certain birth defects, such as heart defects, may require surgery. For many individuals, assistive reproductive technology may be able to help with fertility.

What is the prognosis for an individual with Turner Syndrome?

With appropriate medical care, many individuals with Turner syndrome have essentially normal lifespans.

Other names for
Monosomy X

  • Turner syndrome


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