46,XX intersex

Three main categories have been used to describe DSD in the 46,XX individual:

 1) disorders of gonadal (ovarian) development:

• ovotesticular DSD, previously named true hermaphroditism,
• testicular DSD, previously named XX males,
• gonadal dysgenesis;

 2) disorders related to androgen excess

• congenital adrenal hyperplasia
• aromatase deficiency
• P450 oxidoreductase deficiency.

 3) other rare disorders.

Physiopathology

The most important genes controlling the initial phase of gonadal development, identical in females and males, are Wilms’ tumor suppressor 1 (WT1) and steroidogenic factor 1 (SF1).

Four genes are likely to be involved in the subsequent stages of ovarian development (WNT4, DAX1, FOXL2 and RSPO1), but none is yet proven to be the ovarian determining factor.