What is Turner syndrome?

Causes and Symptoms

Turner syndrome affects an estimated one out of every 2,500 girls born. The disorder is congenital, which means that it begins at conception. Normal males have one X and one Y chromosome. Normal females have two X chromosomes. Females with Turner syndrome have only one X chromosome (an XO pattern) in each of their cells or two X chromosomes with one being incomplete. Although the exact cause is unknown, scientists believe that the disorder may result from an error during the division of the parent’s sex cells.

Shortness is the most common feature of Turner syndrome. The average height of a woman with this condition is 4 feet, 8 inches. Other physical features associated with the syndrome include puffy hands and feet at birth, a webbed neck, prominent ears, a low hairline at the back of the neck, drooping eyelids, dry eyes, flat and broad chest, soft fingernails that turn up at the end, and vaginal dryness.

Ovaries may or may not develop in those with Turner syndrome, and most patients experience ovarian failure. Since the ovaries normally produce estrogen, girls and women with Turner syndrome lack this essential hormone, resulting in infertility, incomplete sexual development, and increased risk of osteoporosis.

Cardiovascular disorders are the single source of increased mortality in patients with Turner syndrome. Women with Turner syndrome are at higher risk of hypertension, renal abnormalities, type 2 diabetes, hypothyroidism, ear infection, diabetes, obesity, cataracts, and celiac sprue.

Treatment and Therapy

No treatment is available to correct the chromosome abnormality that causes this condition. Nevertheless, early injections of human growth hormone can restore much of the growth deficit. Unless they take hormone therapy, women and girls with Turner syndrome will not menstruate or develop breasts and pubic hair. Hormone therapy also reduces the risk of bone loss. Although infertility cannot be altered, pregnancy may be possible through in vitro fertilization. Girls and women with Turner syndrome should be monitored and treated for associated conditions.

Perspective and Prospects

Turner syndrome was first identified by Henry Turner in 1938. In 1959, C. E. Ford discovered that a chromosomal abnormality involving sex chromosomes causes the syndrome.

Bibliography

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Rosenfeld, Ron G., and Melvin M. Grumbach, eds. Turner Syndrome. New York: Marcel Dekker, 1990.

"What is TS?" Turner Syndrome Society of the United States, 2011.