SRY-positive 46,XX male with cryptorchidism as the only presenting clinical feature

Cytogenic and molecular analyses of 46,XX male syndrome with clinical comparison to other groups with testicular azoospermia of genetic origin

BACKGROUND/PURPOSE

XX male is a rare sex chromosomal disorder in infertile men. The purpose of this study was to distinguish the clinical and genetic features of the 46,XX male syndrome from other more frequent, testicular-origin azoospermic causes of male infertility.

METHODS

To study 46,XX male syndrome, we compared clinical and endocrinological parameters to other groups with testicular-origin azoospermia, and to an age-matched group of healthy males and females as normal control. Fluorescent in situ hybridization for detection and localization of the sex-determining region of the Y gene (SRY), array-based comparative genomic hybridization screening, and real-time qualitative polymerase chain reaction of FGF9, WT1, NR5A1, and SPRY2 genes were performed in this genetic investigation.

RESULTS

Our three patients with 46,XX male syndrome had a much higher follicular-stimulating hormone level, lower body height, lower testosterone level, and ambiguous external genitalia. One of the three patients with 46,XX male syndrome was SRY-negative. A further genetic study, including a comparative genomic hybridization array and real-time polymerase chain reaction, showed a gain of FGF9 copy numbers only in the SRY-negative 46,XX male. The genetic copy number of the FGF9 gene was duplicated in that case compared to the normal female control and was significantly lower than that of the normal male control. No such genomic gain was observed in the case of the two SRY-positive 46,XX males.

CONCLUSION

Similar to clinical manifestations of 46,XX male syndrome, genetic evidence in this study suggests that FGF9 may contribute to sex reversal, but additional confirmation with more cases is still needed.

46, XX SRY-positive male syndrome presenting with primary hypogonadism in the setting of scleroderma

OBJECTIVE

To describe a case of SRY gene translocation in a man with scleroderma presenting with primary hypogonadism.

METHODS

We present the clinical, physical, laboratory, and pathologic findings of the study patient and discuss the cytogenetic analysis and the cause of the sexual dysfunction. Relevant literature is reviewed.

RESULTS

A 35-year-old man with a recent diagnosis of diffuse cutaneous sclerosis was referred by his rheumatologist because of a low testosterone level. His medical history was notable for right cryptorchidism corrected after birth. He had no history of sexual activity, but reported normal erectile function before his current presentation. Physical examination findings were remarkable for a height of 157.5 cm; weight of 72.7 kg; extensive, diffuse thickening of the skin; mild gynecomastia; little axillary and pubic hair; and soft testes (1-2 mL bilaterally). Initial laboratory testing revealed the following values: follicle-stimulating hormone, 22.1 mIU/mL (reference range, 1.4-18.1 mIU/mL); luteinizing hormone, 19.7 mIU/mL (reference range, 1.5-9.3 mIU/mL); total testosterone, 25 ng/dL (reference range, 241-827 ng/dL); and free direct testosterone, 0.8 pg/mL (reference range, 8.7-25.1 pg/mL). Laboratory test results were consistent with primary hypogonadism. A urologist performed testicular biopsy, which showed severe testicular atrophy with absent spermatogenesis. Primary hypogonadism due to Klinefelter syndrome or testicular fibrosis secondary to scleroderma was suspected. Karyotype analysis showed a 46, XX karyotype, and fluorescence in situ hybridization was consistent with a 46, XX, Xp22.3(SRY+) gene translocation. After a normal prostate-specific antigen level was documented, testosterone replacement therapy was initiated, and he was referred for genetic counseling.

CONCLUSIONS

The 46, XX SRY-positive male syndrome is rare. Adult diagnosis can be challenging because of normal sexual development. Scleroderma, which rarely can occur in Klinefelter-type syndromes, further complicated the diagnosis in this case.

Molecular evaluation of the SRY gene for gonads of patients with mixed gonadal dysgenesis

AIM

To determine whether the SRY gene is present in the gonads of patients with mixed gonadal dysgenesis (MGD).

METHODS

Molecular analysis was performed in three patients with MGD. Polymerase chain reactions were used to test for the presence of the SRY gene in the peripheral lymphocytes, testes and streak gonads.

RESULTS

Chromosome analysis revealed 45,XO/46,XY in two patients, and 46,XY in the third patient. In the peripheral lymphocytes and testicular tissue, the SRY sequences were positive in all cases. However, the SRY sequence was detected in the streak gonad in only two of the three patients.

CONCLUSIONS

It is interesting that we identified both SRY-positive and SRY-negative streak gonads. Although the SRY gene has a very important role in testicular differentiation, genes other than the SRY gene might also influence the development of the indifferent gonad in MGD.

Three new 46,XX male patients: a clinical, cytogenetic and molecular analysis

BACKGROUND

XX males range phenotypically from completely masculinised individuals to true hermaphrodites and include a subset of SRY negative patients. The correlation between genotype (SRY+/-) and phenotype is still unclear.

AIM

To report three new patients with this rare condition, one of whom was diagnosed prenatally and another was SRY negative, and to verify in our patients whether the presence of SRY results in a more masculinised phenotype.

PATIENTS AND METHODS

We present two phenotypically normal XX male patients (10 and 13.5 years) and one 3.1 years old XX male with ambiguous external male genitalia Prader IV. The patients were diagnosed by clinical, hormonal, sonographic, genetic and histological criteria.

RESULTS

Basal hormonal status was normal for phenotype but an excessive response to GnRH testing was noticed in the second patient together with insufficient hCG stimulation in all three patients. Pelvic ultrasound displayed male structures without Müllerian ducts; testicular biopsy, performed only in the intersex patient, showed Sertoli and Leydig cell hypoplasia. Chromosome analysis confirmed 46,XX karyotype. FISH analysis and molecular analysis by PCR were positive for Yp fragments/SRY gene on Xp in two patients and negative in the patient with ambiguous external genitalia.

CONCLUSIONS

In our observation Y chromosome-specific material containing the SRY gene translocated to the X chromosome results in a completely masculinised phenotype. In the intersex patient, incomplete masculinisation without SRY suggests a mutation of one or more downstream non-Y testis-determining genes.