Androgen Insensitivity Syndrome (AIS)

Description:

Androgen Insensitivity Syndrome (AIS) is a genetic condition that affects sexual development in individuals with XY chromosomes. It is characterized by a partial or complete resistance to the effects of androgens, resulting in varying degrees of feminization of external genitalia, breast development, and lack of menstruation.

Causes:

AIS is caused by mutations in the androgen receptor gene, which interfere with the normal functioning of androgens. These mutations prevent the body’s cells from responding appropriately to male sex hormones, resulting in impaired development of male reproductive structures.

Classification:

AIS is classified into three main subtypes based on the severity of androgen resistance:

• Complete Androgen Insensitivity Syndrome (CAIS): Individuals with CAIS have a complete inability to respond to androgens and typically develop external genitalia that appear female. They often have female secondary sexual characteristics, such as breast development, but lack a uterus and fallopian tubes.
• Partial Androgen Insensitivity Syndrome (PAIS): PAIS is characterized by partial resistance to androgens, resulting in a wide range of genital ambiguity. Individuals with PAIS may have atypical genitalia that do not clearly align with typical male or female structures.
• Mild Androgen Insensitivity Syndrome (MAIS): MAIS is the mildest form of AIS, where individuals have minimal or subtle signs of androgen resistance. These individuals may have normal male external genitalia but can experience infertility or other subtle abnormalities related to androgen insensitivity.

Diagnosis:

AIS is often diagnosed during infancy or adolescence when atypical development is noticed. It is typically confirmed through genetic testing, which identifies mutations in the androgen receptor gene or other related genes.

Treatment:

The management of AIS depends on the individual’s specific needs and desires. Options may include hormonal therapy to induce puberty and promote secondary sexual characteristics, surgical interventions to address genital ambiguity, and counseling to address psychological and emotional aspects associated with sexual development.