Frasier syndrome is characterised by the association of male pseudohermaphrodism and glomerular nephropathy. This syndrome is associated with a high risk of developing gonadoblastoma. Prevalence of this rare disease is unknown. Patients with Frasier syndrome present with normal female external genitalia and streak gonads, and have a 46,XY karyotype. Nephropathy presents during childhood with proteinuria and nephrotic syndrome, and progresses to end-stage renal disease in adolescence or adulthood. Heterozygous mutations in the WT1 gene have been found in women affected by Frasier syndrome. The WT1 gene contains 10 exons and codes for a zinc-finger DNA-binding protein. This protein plays an important role in renal and gonadal development. Mutations responsible for Frasier syndrome are located in intron 9, an alternative splicing site, and lead to the loss or haploinsufficiency of the WT1+KTS isoform, a transcription factor. Histologically, glomerular lesions are not specific. They consist of minimal glomerular lesions associated with segmental and focal glomerular hyalinosis. In women, the diagnosis may be made during investigation for primary amenorrhea, or, in some cases, after renal transplant when nephropathy has progressed to renal failure.
Last update: February 2007