SRY Gene Evaluation in Patients with the Disorders of Sexual Differentiation

Lee, Min Chong; Han, Sang Won; Lee, Jin Sung; Choi, Seung Kang

Abstract

The disorders of sexual differentiation occurred due to the incompatibility of chromosomal sex, gonadal sex and phenotypic sex. A gene within Y chromosome such as SRY gene has been searched to explain this phenomenon. We report cases of defective sexual differentiation, where it is difficult to diagnose with Giemsa stain of Y chromosome alone but SRY gene evaluation was helpful in the diagnosis and treatment of these cases. Genomic DNA from WBC was extracted. XES 10 and XES 11 were used as primers in separately SRY gene by electrophoresis. A positive SRY gene facilitated in confirming the diagnosis of the following cases: Klinefelter`s syndrome with a positive SRY gene originally diagnosed as 46 XX male, Klinefelter`s syndrome with 46XX,a positive SRY gene that was thought to be chordee without hypospadias. Turner`s syndrome that was difficult to be diagnosed due to 46XY, a positive SRY gene, however, SRY gene detection was helpful to detect germ cell tumor development early. 46XX hermaphroditism without SRY gene was diagnosed as true intersex after pathologic examination. Two cases of 46XY hermaphroditism with SRY gene were diagnosed finally as 46 XY true intersex and mixed gonadal dysgenesis each other. Congenital adrenal hyperplasia and androgen receptor defect were confirmed by traditional methods such as hormonal tests and radiologic findings. SRY gene evaluation facilitated in identifying the pathophysiology of many defective sexual differentiations, however, this alone had a limit to explain all these cases. So future research into genes in the autosome, sex chromosome and Z protein will help in the diagnosis and treatment of patients with the disorders of sexual differentiation.