High frequency of Y chromosome microdeletions in male infertility patients with 45,X/46, XY mosaicism

The mosaic 45,X/46,XY karyotype is a common sex chromosomal abnormality in infertile men. Males with this mosaic karyotype can benefit from assisted reproductive therapies, but the transmitted abnormalities contain 45,X aneuploidy as well as Y chromosome microdeletions. The aim of this study was to investigate the clinical and genetic characteristics of infertile men diagnosed with 45,X/46,XY mosaicism in China. Of the 734 infertile men found to carry chromosomal abnormalities, 14 patients were carriers of 45,X/46,XY mosaicism or its variants, giving a prevalence of 0.27% (14/5269) and accounting for 1.91% (14/734) of patients with a chromosomal abnormality. There were ten cases (71.43%, 10/14) of 45,X mosaicism exhibiting AZF microdeletions. Case 1 and Case 4 had AZFc deletions, and the other eight cases had AZFb+c deletions. A high frequency of Y chromosome microdeletions were detected in male patients with 45,X/46,XY mosaicism. Preimplantation genetic diagnosis should be offered to men having intracytoplasmic sperm injection for hypospermatogenesis caused by 45,X/46,XY mosaicism, to avoid the risk of transfering AZF microdeletions in addition to X monosomy in male offspring.

45,X/46,XY Mosaicism in an 18-year-old girl with primary Amenorrhea: A case report / Journal of the ASEAN Federation of Endocrine Societies

@#45,X/46,XY mosaicism is a rare disorder with a wide heterogeneity in its manifestations. An 18-year-old girl was referred to the endocrine clinic for investigation of her primary amenorrhea. Clinical examination was unremarkable. Hormonal profile was consistent with primary ovarian insufficiency and human chorionic gonadotropin (hCG) stimulation did not show evidence of active testicular tissue. Karyotyping studies by G-banding revealed a 45,X/46,XY karyotype. She was diagnosed with mosaic Turner syndrome with Y chromosomal material and investigation was performed to identify the presence of male gonads due to the risk of gonadal malignancy. Magnetic resonance imaging (MRI) of the pelvis did not show evidence of gonads. Laparoscopic exploration was proposed but the patient and parents refused opting for conservative management. This case highlights the challenges in the management of this rare condition.