Turner syndrome and genetics
Turner syndrome is a genetic condition resulting from a chromosomal abnormality, specifically the loss or alteration of one of the X chromosomes, affecting approximately 1 in 2,500 females. First described by clinician Henry H. Turner in 1938, this syndrome is characterized by symptoms such as short stature, ovarian failure, and various physical features like a webbed neck and puffy hands and feet. While the exact cause of the chromosomal error remains unknown, it occurs spontaneously during meiosis and is not inherited.
Diagnosis typically involves chromosomal analysis and additional tests to assess hormone levels and heart health. Although there is no cure for the chromosomal abnormality, treatments like growth hormone therapy and estrogen replacement can address some of the associated physical and developmental challenges. Importantly, individuals with Turner syndrome can lead fulfilling lives and may pursue options like in vitro fertilization for pregnancy. Support from family and organizations such as the Turner Syndrome Society is vital for fostering a positive self-image and identity among those affected.
Turner syndrome and genetics
DEFINITION Turner syndrome is caused by a chromosomal abnormality and is one of the most common genetic problems in women, affecting 1 out of every 2,500 women born, according to the National Institutes of Health. Henry H. Turner, an eminent clinical endocrinologist, is credited with first describing Turner syndrome. In 1938, he published an article describing seven patients, ranging in age from fifteen to twenty-three years, who exhibited short stature, a lack of sexual development, arms that turned out slightly at the elbows, webbing of the neck, and low posterior hairline. He did not know what caused this condition.
In 1959, C. E. Ford discovered that a chromosomal abnormality involving the sex chromosomes caused Turner syndrome. He found that most girls with Turner syndrome did not have all or part of one of their X chromosomes and argued that this missing genetic material accounted for the physical findings associated with the condition.
Risk Factors
Only females are at risk for Turner syndrome. The loss or alteration of the X chromosome that characterizes the disorder is not inherited but takes place spontaneously. For this reason, parents who have one child with Turner syndrome will most likely not have another child with this disorder.
Etiology and Genetics
Turner syndrome begins at conception. The disorder results from an error during meiosis in the production of one of the parents’ sex cells, although the exact cause remains unknown.
Symptoms
Shortness is the most common characteristic of Turner syndrome. The incidence of short stature among women with Turner syndrome is virtually 100 percent. Women who have this condition are, on average, 4 feet 8 inches (1.4 meters) tall. The cause of the failure to grow is unclear. However, growth-promoting therapy with growth hormones has become standard. Most women with the syndrome also experience ovarian failure. Since the ovaries normally produce estrogen, women with Turner syndrome lack this essential hormone. This deficit results in infertility and incomplete sexual development. Cardiovascular disorders are the single source of increased mortality in women with this condition. High blood pressure is common.
Other physical features often associated with Turner syndrome include puffy hands and feet at birth, a webbed neck, prominent ears, a small jaw, short fingers, a low hairline at the back of the neck, and soft fingernails that turn up at the ends. Some women with Turner syndrome have a tendency to become overweight. Many women will exhibit only a few of these distinctive features, and some may not show any of them. This condition does not affect general intelligence. However, another possible symptom is poor spatial perception abilities. For example, women with this condition may have difficulty driving, recognizing subtle social clues, and solving nonverbal mathematics problems; they may also suffer from clumsiness and attention deficit disorder.
Screening and Diagnosis
Girls suspected of having Turner syndrome, usually because of their short stature, often undergo chromosomal analysis. A simple blood test and laboratory analysis called a karyotype are done to document the existence of an abnormality.
Additional tests to diagnose Turner syndrome include measuring blood hormone levels, an echocardiogram (the use of ultrasound to measure heart defects), ultrasound examinations of reproductive organs and kidneys, and a pelvic exam. Pregnant women can receive chromosome analysis to determine whether their children will have the disorder.
Researched in 2023 concluded that identifying Turner Syndrome is more difficult than previously thought and stressed the need for prenatal screening. Doing so would ensure that treatments could begin as soon as possible.
Treatments and Therapy
No treatment is available to correct the chromosome abnormality that causes this condition. However, injections of human growth hormone can restore most of the growth deficit. Unless they undergo hormone replacement therapy, girls with Turner syndrome will not menstruate or develop breasts and pubic hair. In addition to estrogen replacement therapy, women with Turner syndrome are often advised to take calcium and exercise regularly. Researchers believe that the possibility of adding testosterone needs to be studied. Although infertility cannot be altered, pregnancy may be made possible through in vitro fertilization and embryo transfer. Individuals with Turner syndrome can be healthy, happy, and productive members of society.
Nevertheless, because of its relative rarity, a woman with Turner syndrome may never meet another individual with this condition and may suffer from self-consciousness, embarrassment, and poor self-esteem. The attitudes of parents, siblings, and relatives are important in helping develop a strong sense of identity and self-worth. The Turner Syndrome Society of the United States is a key source of information and support groups.
Prevention and Outcomes
Although there is no treatment to cure the chromosomal abnormality, advances in chromosomal analysis have proved helpful in the diagnosis and management of Turner syndrome. In addition, new developments in hormonal therapy for short stature and ovarian failure, combined with advances in in vitro fertilization, have significantly improved the potential for growth, sexual development, and fertility for afflicted individuals.
Bibliography
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Goldstein, Sam, and Cecil R. Reynolds. Handbook of Neurodevelopmental and Genetic Disorders in Children. New York: Guilford, 2011. Print.
Gould, Harley N., et al. "High Levels of Education and Employment Among Women with Turner Syndrome." Journ. of Women's Health 22.3 (2013): 230–35. Print.
Gravholt, Claus A., et al. "The Changing Face of Turner Syndrome." Endocrine Reviews, vol. 44, no. 1, Feb. 2023, pp. 33-69, doi.org/10.1210/endrev/bnac016. Accessed 5 Sept. 2024.
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Power, Theresa, et al. "The Forensic Implications of Turner's Syndrome." Journ. of Forensic Sciences 59.3 (2014): 671–75. Print.
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