Endocrine Abstracts

The decision to be male or female takes place in the developing gonad. Evidence suggests that a number of testis and ovary promoting genes, such as Sox9, Fgf9 and Wnt4, are active at a low level in the indifferent gonad. In XX development Wnt4 expression is maintained and Sox9 and Fgf9 are extinguished. In an XY embryo, Sry is expressed at a critical time to boost Sox9 expression above a critical threshold level, such tha...

It is now 15 years since the discovery of Sry as the primary “testis-determining gene” and Koopman et al.’s classic experiment showing that transgenic expression of Sry in XX mice results in testis development and a male phenotype. Although studies in mice are continuing to provide exciting information about the biology of sex development, significant progress is also being made in our understanding of the molecular mechanisms of gonad devel...

Disorders of sex development (DSD, previously termed intersex disorders) embrace a broad range of pathologies encompassing the undervirilised male, the virilised female, true hermaphroditism (defined by the presence of ovotestes) and sex reversal (e.g. 46XX male). For those infants born with genital abnormalities that make immediate gender assignment not possible, there is an urgent need for specialist input to achieve a diagnosis and develop a management plan. The DSD team wi...