46,XX type pure gonadal dysgenesis

The 46,XX type pure gonadal dysgenesis is usually an autosomal recessive disorder, but, less frequently, may be due to an abnormality of the X chromosome, possibly as a mosaic 45,X cell line confi ned to the gonad.

Deletions of the short or long arm of an X chromosome have been identified in some cases. Such patients have greater ovarian development than those with 46,XY pure gonadal dysgenesis or Turner syndrome and present more often with signs of ovarian dysfunction (secondary amenorrhea or infertility) rather than primary gonadal failure (primary amenorrhea).

Some patients may also have mosaic cell lines with the SRY gene absent in some tissues (peripheral leukocytes), but present in others (testicular tissue).

Tumor predisposition

Patients with 46,XX pure gonadal dysgenesis, as those with Turner syndrome, only rarely have gonadal tumors. Some have had hilus cell hyperplasia and hilus cell tumors with the usual associated virilizing effects. Epithelial tumors are extremely rare, but of these mucinous tumors occur more frequently than serous.

Rare examples of germ cell tumors have been reported, and even though no identifi able Y chromosome component could be detected in some, the possibility of
a cryptic Y fragment cannot be excluded.

See also

 pure gonadal dysgenesis

• 46,XY type pure gonadal dysgenesis