Turner syndrome is a genetic disorder that affects females. Physical features include short stature, infertility, scoliosis, kidney problems, extra neck skin, and swelling of the hands and feet. People with Turner syndrome are usually normal intellectually, but some may experience developmental delay and/or learning disabilities.
The worldwide incidence of Turner syndrome is approximately 1 in 2,500 live female births. The disorder is caused by missing genetic material, which currently cannot be replaced. Treatment is therefore focused on managing the syndrome. For example, some girls may undergo hormone treatment, allowing them to go through puberty.
Turner Syndrome and Mosaic Turner Syndrome
People typically have 23 pairs of chromosomes in most of their cells, including a pair involved in sex determination. These are the sex chromosomes, X and Y: females typically have two X chromosomes, and males have one X and one Y.
Turner syndrome occurs when a female is missing an X chromosome in her somatic (body) cells. The syndrome can also occur when a female has two X chromosomes in her somatic cells, one of which is abnormal in structure.
The X chromosomes carry genes involved in stature, development of the ovaries, and production of sex hormones. When these instructions are missing, products such as proteins don’t get made, resulting in the features of Turner syndrome. If only some cells are affected, the condition is called mosaic Turner syndrome.
Is Turner Syndrome Inherited?
Inheritance of Turner syndrome is possible but very unlikely. Spontaneous cell division errors can occur early in embryonic development, or during sex cell formation. Such errors can result in extraneous or missing chromosomes.
Genetic Testing of Turner Syndrome
Turner syndrome can be detected with a chromosome analysis test, and prenatal testing is also possible. Genetic counseling may be an option for individuals or families seeking information on chromosomal disorders.
Visit the Turner Syndrome Society of the United States website for more information on the diagnosis and treatment of Turner syndrome. For the basics of chromosomes, read Introduction to Chromosomes in Human Cells and Introduction to Chromosome Abnormalities.
Sources
“Genetic Features of Turner Syndrome”, National Institute of Child Health and Human Development website, accessed: 23rd May 2010, no author specified.
“Learning About Turner Syndrome”, last updated: 11th December 2009, National Human Genome Research Institute website, accessed: 23rd May 2010, no author specified.
“Turner syndrome”, published: 17th May 2010, Genetics Home Reference website, accessed: 23rd May 2010, no author specified.
“Turner Syndrome – XO Syndrome”, last updated: June 2007, Centre for Genetics Education website, accessed: 23rd May 2010, author: Barlow-Stewart, Kristine.
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