The Clinical Manifestation and Genetic Evaluation in Patients with 45,X/46,XY Mosaicism.

45,X/46,XY mosaicism is a rare chromosomal abnormality and probably underdiagnosed. Although clinical and genetic analyses have been performed in some disorders of sexual development, there have been few studies focusing on the phenotype and genetic details of 45,X/46,XY mosaicism, especially in the Chinese population. The aim of this study was to describe the experience of our service in relation to 16 cases with 45,X/46,XY mosaicism. The age at the first evaluation of the patients ranged from 43 days to 30 years. Eight patients were reared as female and 8 as male. The main reasons for examination were primary amenorrhea, sterility, or ambiguous genitalia. Short stature was more common in female than in male patients. Two patients accepted gonadectomy due to tumor risk and none presented gonadal malignancy. The SRY gene was amplified positively in all of the patients. AZF gene microdeletions were present in 6 of 8 male patients, and all adult male patients had no sperm. No correlation has been found between clinical manifestations and the proportion of mosaic cells in peripheral blood. Our observations may permit a better management of people with 45,X/46,XY mosaicism.