Turner syndrome (TS) occurs in approximately one out of every 2,000- 4,000 female live births. It is a chromosomal condition describing girls and women with common features, physical traits, and medical conditions caused by the complete or partial absence of the second sex chromosome. TS was first described in the United States in 1938 by Dr. Henry Turner.
At the basic level, the missing genetic material prevents the female body from growing and maturing naturally. Turner syndrome is variable, and each girl and woman will have unique health needs and characteristics. Most girls and women have two complete X chromosomes (the sex chromosomes for females). Turner syndrome is caused by the absence of all or part of the second sex chromosome in some or all of the cells of the body. The most consistent features of TS are short stature and lack of ovarian development, however, there are other symptoms and characteristics that can appear in varying degrees, depending on each person's unique genetic makeup.
What Causes Turner Syndrome?
Turner syndrome occurs when all or part of one of the X chromosome is lost before or soon after the time of conception.
There is nothing that either parent did before or at the start of the pregnancy that caused or increased the risk of TS for their daughter. The age of a parent, ethnicity, diet, or other factors are unrelated to the conception of a child with Turner syndrome.
Almost 50% of those with TS are missing the X chromosome in all of the cells that are tested (usually blood cells). This is written 45X and the medical term is monosomy X.
About 30% of those with TS have what is called mosaicism. This means that some cells have the complete number of chromosomes, written 46,XX, and the other cells are missing an X. It is believed that mosaicism is a result of the loss of an X chromosome after fertilization. For more information Click Here
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