What is the Difference Between Androgen Insensitivity Syndrome and Mullerian Agenesis?

Androgen Insensitivity Syndrome (AIS) and Müllerian Agenesis are two distinct congenital disorders that may present with similar symptoms, such as primary amenorrhea. However, they have different underlying causes and characteristics:

Androgen Insensitivity Syndrome (AIS):

AIS is a genetic condition due to androgen receptor dysfunction, predominantly seen in males.
It is characterized by the partial or complete inability of cells to respond to androgens.
Individuals with AIS may have a female or ambiguous genitalia, and the gonads are testes, which produce normal androgens.

Müllerian Agenesis:

Müllerian Agenesis is a congenital disorder characterized by the failure of the Müllerian duct to develop, resulting in the absence or underdevelopment of the vagina, uterus, or both.
It affects females and is caused by embryologic underdevelopment of the Müllerian duct.
Patients with Müllerian Agenesis have normal height, breast development, body hair, and external genitalia.

Both conditions can be diagnosed through physical examinations, blood tests, and imaging scanning, and they can be treated through specific surgeries. The key difference between Androgen Insensitivity Syndrome and Müllerian Agenesis is that AIS is caused by the inability of cells to respond to androgens, while Müllerian Agenesis is caused by the failure of the Müllerian duct to develop. Furthermore, AIS mainly affects males, while Müllerian Agenesis mainly affects females.

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What is the Difference Between Androgen Insensitivity Syndrome and Mullerian Agenesis?

Comparative Table: Androgen Insensitivity Syndrome vs Mullerian Agenesis

Androgen Insensitivity Syndrome (AIS) and Müllerian Agenesis are two different congenital disorders that may present with similar symptoms, such as primary amenorrhea. Here is a comparison table of the differences between the two conditions:

Feature	Androgen Insensitivity Syndrome (AIS)	Müllerian Agenesis
Genetics	Predominantly seen in males, due to androgen receptor dysfunction.	Predominantly seen in females, characterized by the failure of the Müllerian ducts to develop.
Genotype	Genotype XY.	Genotype XX.
Serum T Levels	Normal male T levels.	Normal female T levels.
Pubic and Axillary Hair	Decreased pubic and axillary hair in AIS.	Normal female pubic and axillary hair.
Height	Increased height compared with female counterparts.	Normal female height.
Vaginal and Uterine Development	Vagina may be shortened and may appear as a dimple, with no uterus and intraabdominal testes.	Vagina is present and may appear as a small flush dimple or longer, without a cervix at the vaginal apex, and may be shortened.
Diagnosis	The diagnosis can be confirmed by testing the CYP17A1 gene and careful interpretation of adrenal hormones, including elevated serum deoxycorticosterone and corticosterone levels and low cortisol, androgens, and estrogen levels.	Diagnosis mainly involves imaging studies such as ultrasound or magnetic resonance imaging (MRI) to delineate internal anatomic structures, and to identify absent or hypoplastic vagina and uterus.

Despite their differences, both conditions can lead to primary amenorrhea and may require further evaluation to determine the underlying cause.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.