Gonadal Function in 15 Patients Associated with WT1 Gene Mutations.

Area of Science:

• Genetics
• Endocrinology
• Pediatric Nephrology

Background:

• Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are rare genetic disorders resulting from mutations in the WT1 gene.
• Both syndromes present with complex phenotypes including renal disease, disorders of sex development, and predisposition to tumors like Wilms' tumor and gonadoblastoma.

Purpose of the Study:

• To investigate the relationship between gonadal function and the phenotype of external genitalia in a cohort of Japanese patients with WT1 gene mutations.
• To clarify overlaps in clinical manifestations and endocrine responses between DDS and FS.

Main Methods:

• Genetic analysis to confirm WT1 mutations in 15 Japanese patients.
• Clinical evaluation of renal disease and external genitalia phenotype.
• Human chorionic gonadotropin (HCG) loading tests to assess serum testosterone (T) response.
• Measurement of dehydroepiandrosterone sulfate (DHEA-S) levels.

Main Results:

• Overlapping phenotypes in external genitalia and renal complications were observed between DDS and FS patients diagnosed genetically.
• Serum testosterone response to HCG stimulation generally correlated with external genitalia phenotype in both DDS and FS, with notable exceptions in one DDS and one FS patient.
• Four FS patients exhibited incomplete pubic hair development and low DHEA-S levels, suggesting potential adrenal involvement.

Conclusions:

• WT1 gene mutations in DDS and FS lead to diverse phenotypes with significant overlap, complicating diagnosis and management.
• Gonadal function, assessed by HCG testing, largely aligns with external genitalia presentation, but individual variations necessitate careful clinical assessment.
• Further research into the endocrine and developmental pathways affected by WT1 mutations is warranted to improve patient care.