Xx male

XX male syndrome is a rare genetic condition where individuals with two X chromosomes in each cell, the pattern typically found in females, have a male physical appearance. XX male syndrome occurs in approximately 1 in 20,000 to 25,000 males.

Causes

XX male syndrome is usually caused by the translocation of a tiny section of the Y chromosome containing the gene SRY (sex-determining region Y) to one of the X chromosomes. The SRY gene initiates male sexual development, which usually occurs in individuals with one X and one Y chromosome. However, in XX male syndrome, even though the individual has two X chromosomes, the presence of the SRY gene leads to male development.

Symptoms

Individuals with XX male syndrome have male sexual characteristics but they are often smaller than average and they may have small testes. They are typically infertile and may have some degree of breast development (gynecomastia). Some individuals with XX male syndrome have ambiguous genitalia or other physical abnormalities.

Diagnosis

The diagnosis of XX male syndrome is based on clinical findings and specialized tests that can detect the presence of the SRY gene on one of the X chromosomes. These tests include karyotyping, a laboratory technique that produces an image of an individual's chromosomes, and fluorescent in situ hybridization (FISH), a test that identifies and maps the genetic material in an individual's cells.

Treatment

There is no cure for XX male syndrome, but treatments can help manage the symptoms. These may include hormone therapy to reduce breast development and promote male secondary sexual characteristics, and surgery to correct physical abnormalities.

See also

• Klinefelter syndrome
• Turner syndrome
• Androgen insensitivity syndrome