Turner's Syndrome
Turner's syndrome (also called Turner syndrome) is a genetic disorder caused by a missing or partially missing X chromosome. It affects only females and typically causes a variety of pbysical abnormalities. Girls and women with Tirner's syndrome usually are short, their ovaries and breasts fail to develop normally, and they are almost always infertile.
What Is Turner's Syndrome?
Turner's syndrome is a genetic disorder that occurs when one of a girl's X chromosomes is partially or completely missing. Almost every cell in a person's body (except for eggs and sperm cells) has 23 pairs of chromosomes. One pair, the sex chromosomes, makes a person male or female: Boys have an X and a Y chromosome (XY), whereas girls have two X chromosomes (XX). The chromosomes contain all of the information the body needs to function and to develop properly. If part of a chromosome is missing, as in Turner's syndrome, the important information on that chromosome is also missing.
How a girl's body is affected physically by Turner's syndrome depends on how much of the chromosome is missing. Some girls have a mild form of the syndrome that is not detected until they are teenagers or adults. If untreated, nearly all girls with Turner's syndrome grow slowly and reach a short adult height, and their breasts do not enlarge, and they do not
have menstrual periods as is normal for adolescent girls. Some may have additional problems, including the following:
* abnormalities in appearance
* hearing loss
* obesity
* heart disorders
* kidney disorders
* thyroid disorders
Most of the physical conditions are treatable, and with good consistent medical care, a person with Turner's syndrome can have a fully productive life and normal life span. Most people with Turner's syndrome have normal intelligence, but some may have specific learning problems, especially with math.
It is believed that approximately 98 percent of pregnancies in which the mother is carrying a fetus with the genetic defect that would become Turner's syndrome will spontaneously end in miscarriage.
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