Study On The Relationship Between SRY, AR, RSPO1 Gene And Disorders Of Sexual Development

ObjectiveTo investigate the relationship between SRY gene and abnormal sexual development, ARgene and complete androgen insensitivity syndrome and its molecular genetic mechanisms,RSPO1 gene and 46,XX male sex disorder.Methods13 cases with abnormal sex development were selected for further study on cytogenetics,molecular genetics and histological examination according to their clinical histories, hormonalprofiles and ultrasonography. The peripheral blood and testicular tissue were used and thedetections were as follows:1.Chromosome analyses were performed by G-banding.2. SRY, AR and RSPO1 genes were amplified by polymerase chain reaction.3. DNA sequencing was carried out with an ABI PRISM 3730 DNA sequencer to detect themutations of SRY, AR and RSPO1 genes.4. HE and immunohistochemistry staining were performed on surgical excision of testiculartissue.Result1. Among the 13 cases, 11 were female with 46,XY keryotype, two were male with 46,XXkeryotype. SRY gene was positive in 10 cases of XY female and negative in one case of XYfemale. No mutation was found in SRY gene in any of the 10 cases by DNA sequencing. Twocases were confirmed as complete androgen insensitivity syndrome by DNA sequencing of ARgene.2. Each of the two cases with complete androgen insensitivity syndrome revealed a novel mutation in the AR gene. One was a C to A transition at position 749 in exon 1, another was a Ato T transition at position 72 in exon 3. In one case of resected testicular tissue, HE stainingshowed the seminiferous tubules were totally filled with Sertoli cells without germ cells, theinterstitium contained hyperplastic clusters of Leydig cells. Immunohistochemistry stainingshowed moderate positivity in the nuclei of Sertoli cells, strong positivity in the nuclei ofperitubular myoid cells, no positivity in the majority of nuclei of Leydig cells, only a few withrandom distribution.3. SRY gene was negative and RSPO1 gene was positive in the two cases with 46, XX male. Among thetwo, one was identified GC32>AT mutations in intron 5 in the RSPO1 gene.ConclusiConclusion1. Mutations in the AR gene are the cause of complete androgen insensitivity syndrome,leading to the impairment or out of the androgen receptor function, which resulted in thecorresponding clinical symptoms . Testicular histology and abnormal expression of AR proteinalso support the above conclusion. The study extends the spectrum of mutations in the AR gene.2. Deletion of SRY gene causes 46, XY female sex reversal, indicating the importance ofSRY gene in sex determination.3. In this study, whether or not the mutations in intron 5 in the RSPO1 gene were the casueof 46, XX male abnormal sexual development need to be further studied.