Partial androgen insensitivity syndrome
| Partial androgen insensitivity syndrome | |
|---|---|
 |
|
| AIS results when the function of the androgen receptor (AR) is impaired. The AR protein (pictured) mediates the effects of androgens in the human body. | |
| Classification and external resources | |
| Specialty | endocrinology |
| ICD-10 | E34.52 |
| ICD-9-CM | 259.52 |
| OMIM | 312300 300068 |
| DiseasesDB | 29662 12975 |
| eMedicine | ped/2222 |
| MeSH | D013734 |
| GeneReviews | |
Partial androgen insensitivity syndrome (PAIS) is a condition that results in the partial inability of the cell to respond to androgens. The partial unresponsiveness of the cell to the presence of androgenic hormones impairs the masculinization of male genitalia in the developing fetus, as well as the development of male secondary sexual characteristics at puberty, but does not significantly impair female genital or sexual development. As such, the insensitivity to androgens is only clinically significant when it occurs in genetic males (i.e. individuals with a Y chromosome, or more specifically, an SRY gene).
PAIS is one of three types of androgen insensitivity syndrome, which is divided into three categories that are differentiated by the degree of genital masculinization: complete androgen insensitivity syndrome (CAIS) is indicated when the external genitalia is that of a normal female, mild androgen insensitivity syndrome (MAIS) is indicated when the external genitalia is that of a normal male, and partial androgen insensitivity syndrome (PAIS) is indicated when the external genitalia is partially, but not fully masculinized.
Androgen insensitivity syndrome is the largest single entity that leads to 46,XY undermasculinization.
A supplemental system of phenotypic grading that uses seven classes instead of the traditional three was proposed by pediatric endocrinologist Charmian A. Quigley et al. in 1995. The first six grades of the scale, grades 1 through 6, are differentiated by the degree of genital masculinization; grade 1 is indicated when the external genitalia is fully masculinized, grade 6 is indicated when the external genitalia is fully feminized, and grades 2 through 5 quantify four degrees of increasingly feminized genitalia that lie in the interim. Grade 7 is indistinguishable from grade 6 until puberty, and is thereafter differentiated by the presence of secondary terminal hair; grade 6 is indicated when secondary terminal hair is present, whereas grade 7 is indicated when it is absent. The Quigley scale can be used in conjunction with the traditional three classes of AIS to provide additional information regarding the degree of genital masculinization, and is particularly useful when the diagnosis is PAIS.
...
Wikipedia