Webbed neck turner syndrome7/3/2023 For example, an egg or sperm cell may lose a sex chromosome as a result of nondisjunction. An error in cell division called nondisjunction can result in reproductive cells with an abnormal number of chromosomes. When this condition results from monosomy X, the chromosomal abnormality occurs as a random event during the formation of reproductive cells (eggs and sperm) in the affected person's parent. Most cases of Turner syndrome are not inherited. The loss of one copy of this gene likely causes short stature and skeletal abnormalities in women with Turner syndrome. They have, however, identified one gene called SHOX that is important for bone development and growth. Researchers have not determined which genes on the X chromosome are associated with most of the features of Turner syndrome. Women with Turner syndrome caused by X chromosome mosaicism are said to have mosaic Turner syndrome. Some women with Turner syndrome have a chromosomal change in only some of their cells, which is known as mosaicism. Turner syndrome can also occur if one of the sex chromosomes is partially missing or rearranged rather than completely absent. The missing genetic material affects development before and after birth.Ībout half of individuals with Turner syndrome have monosomy X, which means each cell in the individual's body has only one copy of the X chromosome instead of the usual two sex chromosomes. Turner syndrome results when one normal X chromosome is present in a female's cells and the other sex chromosome is missing or structurally altered. People typically have two sex chromosomes in each cell: females have two X chromosomes, while males have one X chromosome and one Y chromosome. Turner syndrome is related to the X chromosome, which is one of the two sex chromosomes. Developmental delays, nonverbal learning disabilities, and behavioral problems are possible, although these characteristics vary among affected individuals. Most girls and women with Turner syndrome have normal intelligence. Complications associated with these heart defects can be life-threatening. One third to one half of individuals with Turner syndrome are born with a heart defect, such as a narrowing of the large artery leaving the heart (coarctation of the aorta) or abnormalities of the valve that connects the aorta with the heart (the aortic valve). A small percentage of females with Turner syndrome retain normal ovarian function through young adulthood.Ībout 30 percent of females with Turner syndrome have extra folds of skin on the neck (webbed neck), a low hairline at the back of the neck, puffiness or swelling (lymphedema) of the hands and feet, skeletal abnormalities, or kidney problems. Many affected girls do not undergo puberty unless they receive hormone therapy, and most are unable to conceive (infertile). The ovaries develop normally at first, but egg cells (oocytes) usually die prematurely and most ovarian tissue degenerates before birth. An early loss of ovarian function (ovarian hypofunction or premature ovarian failure) is also very common. The most common feature of Turner syndrome is short stature, which becomes evident by about age 5. Assisted reproduction techniques can help some women with Turner syndrome get pregnant.Turner syndrome is a chromosomal condition that affects development in females. Hormone replacement can help start sexual development. Growth hormone often helps girls reach heights that are close to average. There is no cure for Turner syndrome, but there are some treatments for the symptoms. Sometimes it is found in prenatal testing. They are at risk for health difficulties such as high blood pressure, kidney problems, diabetes, cataracts, osteoporosis, and thyroid problems.ĭoctors diagnose Turner syndrome based on symptoms and a genetic test. Most women with Turner syndrome are infertile. Short, "webbed" neck with folds of skin from tops of shoulders to sides of neck.Other physical features typical of Turner syndrome are: Girls who have it are short, and their ovaries don't work properly. The cause is a missing or incomplete X chromosome. Turner syndrome is a genetic disorder that affects a girl's development.
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