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A 46,XX SRY-negative man with complete virilization and infertility as the main anomaly
Angelo Valetto1, Veronica Bertini, Erika Rapalini
1Divisione di Citogenetica e Genetica Molecolare, Azienda Ospedaliera Universitaria Pisana, Pisa, Italy.
Objective:
To report a case of a 46,XX SRY-negative man with a male phenotype and azoospermia.
Design:
Case report.
Setting:
Molecular and Cytogenetic Unit in a University Hospital.
Patient(S):
A 35-year-old man with complete masculinization who referred to our institution because of a history of several years of infertility.
Intervention(S):
Lymphocytic karyotype and genetic counseling.
Main Outcome Measure(S):
Peripheral blood metaphases were analyzed by standard G-banding and Q-banding. Fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR) analyses were performed.
Result(S):
Semen analysis showed azoospermia. Chromosome analysis revealed a 46,XX karyotype; molecular and cytogenetic analyses excluded the presence of SRY (the sex-determining region of the Y chromosome) gene.
Conclusion(S):
This case is one of the rare patients reported in the literature in whom testicular differentiation and a complete virilization in a 46,XX chromosomal constitution does not account for a translocation of the SRY gene to the X chromosome or to the autosomes. This finding suggests that other genes downstream from SRY, not yet identified, play an important role in sex determination.
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