Chromosomal disorder (from the presence of only one sex chromosome, X, in all or some of the body's cells) that causes abnormal sexual development in females. The syndrome may include absent or undeveloped ovaries, underdeveloped secondary sex characteristics, low hairline, webbed neck, shield-shaped chest with wide-spaced nipples, and kidney and heart malformations with coarctation (narrowing) of the aorta. It may not be recognized until a girl fails to undergo puberty at a normal age. Estrogen treatment results in puberty, adult appearance, and normal sex drive but not fertility. Surgery can correct malformations.
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Evaluation of delayed puberty usually reveals the presence of pubic hair, but elevation of gonadotropins, indicating that the pituitary is providing the signal for puberty but the gonads are failing to respond. The next steps of the evaluation usually include checking a karyotype and imaging of the pelvis. The karyotype reveals XX chromosomes and the imaging demonstrates the presence of a uterus but no ovaries (the streak gonads are not usually seen by most imaging). At this point it is usually possible for a physician to make a diagnosis of XX gonadal dysgenesis.
The XX gonadal dysgenesis is the related to the Swyer syndrome inasmuch as both conditions have the same phenotype and clinical issues, however in Swyer syndrome the chromosome constellation is 46, XY, and thus requires gonadectomy.
In Turner syndrome there is a demonstrable abnormality in or absence of one of the sex chromosomes that is the cause of the development of gonadal dysgenesis. In contrast XX gonadal dysgenesis has a normal female chromosome situation.
Another type of XX gonadal dysgenesis is known as 46 xx gonadal dysgenesis epibulbar dermoid, which follows the similar symptoms as the regular syndrome, though it also shows signs of epibulbar dermoid (eye disorder). It has been suggested to be a new type of syndrome.
New Gonadal Dysgenesis Study Findings Recently Were Published by Researchers at Murdoch Children's Research Institute.
May 17, 2011; Researchers detail in 'Copy number variation in patients with disorders of sex development due to 46,XY gonadal dysgenesis,' new...
New gonadal dysgenesis data have been reported by researchers at University of Medical Sciences, Faculty of Medicine.
Mar 11, 2010; A report, 'Swyer syndrome in a woman with pure 46,XY gonadal dysgenesis and a hypoplastic uterus: a rare presentation,' is newly...