Turner Syndrome: An Overview

Turner Syndrome is a chromosomal condition first described by Dr. Henry Turner in the 1930's. It affects only females, and is characterized by short stature and the lack of normal sexual development at puberty. Turner Syndrome (TS) affects one in 2,500 live female births and may account for up to 10% of all miscarriages.

The disorder occurs when the DNA is missing the second sex chromosome, or part of the second chromosome is missing. Females carry two X chromosomes in their genetic information, and males carry XY chromosomes. In Turner Syndrome, the female may have only one X chromosome; she may carry two X chromosomes with one only partially complete; or she may have a condition called mosaicism, in which some cells carry two X chromosomes while others carry only one.

TS is not believed to be an inherited genetic condition, but rather a random error that occurs during the formation of either the eggs or sperm of the parents. Since the male partner donates either an X or Y chromosome to the child's DNA, and the mother always contributes an X chromosome, the abnormality may come from either parent. The condition may be diagnosed in utero, after delivery, or during the teen or adult years when signs are subtle. Since TS is a genetic abnormality, the quality of prenatal care does not affect the outcome.

Female infants with this condition are shorter than average at birth, and may have fluid around the neck (cystic hygroma) and swelling of the hands and feet. A broad chest with widely spaced nipples, or specific heart abnormalities may indicate the presence of Turner Syndrome at birth.

The intelligence is usually not affected any more than in the general population, although the girl with TS may have difficulty with spatial-temporal processing (imaging objects in relation to one another), non-verbal memory and attention. This may cause problems with their sense of direction, manual dexterity, and social skills. They may struggle with math; however, their verbal and reading skills are often quite excellent.

The girl may grow at a normal rate until about three years old, then growth slows and she will not have the expected growth spurt at puberty. The ovaries will not produce estrogen and develop eggs, and the girl will not begin having menstrual periods or develop breasts.

Girls diagnosed with Turner Syndrome are usually placed on low-dose estrogen replacement therapy as they reach the age of puberty, usually around 12 years old. Progesterone, and larger doses of estrogen, are given a little later to produce a monthly period, which is necessary to keep the womb healthy. It is unusual for a woman with TS to conceive if she has not received estrogen during these years, but she may be able to have a family through embryo donation and implantation.

Growth hormone injections may be given during childhood to increase the final adult height, which is usually about 4'8" in patients who have received the treatment. Females with Turner Syndrome often exhibit other physical characteristics which are associated with TS, and which may vary in severity between individuals:

A webbed neck (extra folds of skin around the neck)

Facial features such as a narrow, high-arched palate, receding lower jaw; slightly drooping eyes, low-set ears, or low hairline

Scoliosis (curvature of the spine)

Strabismus (lazy eye)

Elbows that turn slightly out to the side, short fourth metacarpals (the ends of the bones that form the knuckles), flat feet, or small, narrow fingernails and toenails that turn up

Females with Turner Syndrome need regular medical check-ups, since they are at higher risk for other medical conditions, including ear infections, hearing loss, hypothyroidism, high blood pressure, and heart and kidney abnormalities. Women diagnosed with TS should receive estrogen therapy until they reach the age of menopause to avoid osteoporosis.

Female infants who are who are diagnosed with TS should receive quality medical care from a pediatric endocrinologist (a specialist in childhood conditions of hormones and metabolism). Early diagnosis, intervention and treatment will allow girls with TS to grow into women who can lead a happy, normal lives.

This article is for information only, and not meant to use as a diagnosis, or to replace the advice of your physician.