Androgen insensitivity syndrome (AIS) is an inherited disorder that affects an individual's sexual development. It occurs when a person's body does not respond to the presence of androgens, which are hormones responsible for the development of male sexual features. AIS is a rare condition, affecting an estimated 1 in 20,000 to 1 in 50,000 people.
Symptoms of Androgen Insensitivity Syndrome
People with AIS may experience a range of symptoms, depending on the type of AIS they have. The most common symptom is a lack of development of male sexual features. This can include a lack of facial and body hair, underdeveloped testes, and an inability to produce sperm. Other symptoms may include an abnormally shaped penis, undescended testes, and infertility.
Types of Androgen Insensitivity Syndrome
There are three types of AIS: complete androgen insensitivity syndrome (CAIS), partial androgen insensitivity syndrome (PAIS), and mild androgen insensitivity syndrome (MAIS). CAIS is the most severe form of the disorder and is characterized by an inability to develop male sex features. PAIS is less severe and may cause a milder form of male sexual development. MAIS is the mildest form and is characterized by a normal male appearance, but may still result in infertility.
Causes of Androgen Insensitivity Syndrome
AIS is caused by a genetic mutation in the androgen receptor gene. This gene is responsible for the body's response to androgens and, when mutated, can cause the body to be unable to respond to the hormones. The mutation is usually passed on from parents to their children.
Diagnosis and Treatment of Androgen Insensitivity Syndrome
AIS is usually diagnosed during childhood, although it can be detected later in life. Diagnosis is typically done through a physical examination and genetic testing. Treatment for AIS depends on the type and severity of the disorder. Hormonal therapy may be used to help with the development of male sexual characteristics, while surgery may be used to correct any physical abnormalities.