TY - CHAP M1 - Book, Section TI - Turner Syndrome A1 - Bondy, Carolyn A. A2 - Murray, Michael F. A2 - Babyatsky, Mark W. A2 - Giovanni, Monica A. A2 - Alkuraya, Fowzan S. A2 - Stewart, Douglas R. Y1 - 2014 N1 - T2 - Clinical Genomics: Practical Applications in Adult Patient Care AB - Disease summary:Caused by complete or partial loss of the second sex chromosome (45,X karyotype).The great majority of 45,X gestations end in fetal demise by end of first trimester.Approximately 1/2500 live born females have Turner syndrome (TS).Extreme short stature may be prevented by growth hormone RX during childhood.Secondary sexual development and normal sexual functioning are achieved with estrogen replacement treatment.The other features if diagnosed and remedied in a timely manner need not impair longevity or quality of life.Hereditary basis:TS is a sporadic disorder occurring due to nondisjunction or fragmentation of sex chromosomes during gametogenesis or early embryonic development.Differential diagnosisNoonan syndrome—the physical phenotype may mimic TS, with short stature and residual evidence fetal lymphedema (eg, neck webbing) and congenital heart disease (CHD). The karyotype of this autosomal dominant syndrome is normal, however.Idiopathic short stature with constitutional delay of puberty—the karyotype in these children is also normal. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessmedicine.mhmedical.com/content.aspx?aid=1102706966 ER -