Table 1.

Examples of 46,XY differences/disorders of sex development (DSD).

Condition	Incidence	Comment	Advantage in sports?
5α-reductase deficiency type 2	Extremely rare with geographical regions of higher incidence	Individuals may be assigned female sex at birth. Virilization proceeds at puberty.	Yes
Partial androgen insensitivity (PAIS)	1/130,000	Ambiguous genitalia at birth. From puberty, high testosterone, but with varying effect depending on androgen receptor sensitivity.	Possibly
17β-hydroxysteroid dehydrogenase type 3 (17β- HSD3) deficiency	1/147,000	Individuals are often raised as girls but undergo virilization at puberty.	Yes
Ovotesticular DSD	1/100,000	The individual has both ovarian and testicular tissue. Born with ambiguous genitalia. Virilization may proceed at puberty.	Possibly