Allie Fitzgerald
BIOL 150
11/22/11
Turner syndrome (TS) is a genetic condition in which a female does not have the usual pair of two X chromosomes (“What is TS?”). This condition was named after Dr. Henry Turner, who was one of the first researchers to describe the features of Turner’s Syndrome in 1930s. TS occurs in about 1 female out of every 2,000 female births, but is much more common in miscarriages. A diagnosis of TS is made through a karyotype test. This is performed on cells in the amniotic fluid before birth and on cells in the blood after. In a karyotype, the chromosomes in the white blood cells of the individual are counted and any abnormalities are noted. The primary characteristics of TS and associated risk factors will be discussed. It is important to know that those with Turner syndrome can live a normal life, but are carefully monitored by their doctor. How is Turner Syndrome a genetic disorder? TS is related to the X chromosome, which is one of the two sex chromosomes ("Turner Syndrome (b)"). There are two sex chromosomes in each cell. These chromosomes differentiated between females and males: females have two X chromosomes and males have one X chromosome and one Y chromosome. Turner syndrome develops when one X chromosome in the female’s cells is missing or has an altered structure. Almost half of individuals with Turner syndrome have monosomy X, which stands for one copy of X chromosome in each cell instead of the normal two X chromosomes. The other half result from one X chromosome having a rearranged structure or a partial piece missing. If some women with TS have a chromosomal change in only some of their cells, this is known as mosaicism. Either way, the lack of a second normal X chromosome (or alteration of it) causes genetic material to be missing, which then affects development of child before and after birth. It has not been determined yet through research which genes on the X chromosome are responsible for
Cited: McKusick, Victor A. "SHORT STATURE HOMEOBOX; SHOX." OMIM - Online Mendelian Inheritance in Man. 12 Jan. 1990. Web. 30 Oct. 2011. . "Turner Syndrome (a)." PubMed Health. A.D.A.M. Medical Encyclopedia, 14 Oct. 2009. Web. 16 Oct. 2011. . "Turner Syndrome (b)." Genetics Home Reference - Your Guide to Understanding Genetic Conditions, May 2008. Web. 16 Oct. 2011. . "Turner Syndrome Symptoms, Causes, Treatment - Is Turner Syndrome Inherited?" MedicineNet.com. National Human Genome Research Institute, 13 May 2008. Web. 16 Oct. 2011. . "What Is TS?" Turner Syndrome Society of the US. Web. 16 Oct. 2011. .