The main factor influencing sex determination of an embryo is the sex-determining region Y (SRY), a master regulatory gene located on the Y chromosome. The presence of SRY causes the bipotential gonad to differentiate into a testis. However, some individuals carry a Y chromosome but are phenotypically female (46,XY females) or have a female karyotype but are phenotypically male (46,XX males). 4...

A case of bilateral gonadoblastoma/dysgerminoma in a 46 XY phenotypical female is presented. Increased circulating beta human chorionic gonadotropin (beta-HCG) and testosterone together with a decreased concentration of follicle stimulating hormone (FSH) reflected the activities of these tumours. The patient is alive and well three years later, after treatment by surgery and cobalt therapy.

the androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. the primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. this prevents normal androgen action and thus leads to impaired virilization. a point m...

A very rare case of complete testicular feminisation with a 47,XXY sex chromosome complement is described. The X-chromatin is positive. The subject studied, who belongs to a family in which four other members have Morris's syndrome and have a 46,XY karyotype, is a perfect phenotypic female. The endocrine situation is unique and resembles, in part, that of subjects with Klinefelter's syndrome.

BACKGROUND Prenatal deficit of androgens or androgen action results in atypical genitalia in individuals with XY disorders of sex development (XY,DSD). XY,DSD include mainly disorders of gonadal development and testosterone synthesis and action. Previously, most XY,DSD individuals were assigned to the female sex. Constructive genital surgery allowing heterosexual intercourse, gonadectomy, and h...

Here we describe a fetus in whom a cystic hygroma was detected by ultrasound during the second trimester. Autopsy demonstrated a female fetus with manifestations of Ullrich-Turner syndrome, including gonadal dysgenesis, generalized lymphedema, and preductal aortic coarctation. Surprisingly, the karyotype was 46,XY, with no evidence of mosaicism for a 45,X cell line. Y-DNA hybridization studies ...

The phenotypic spectrum of 46,XX/46,XY chimeric patients is variable. It ranges from normal male or female genitalia to different degrees of ambiguous genitalia. Chimerism results from the amalgamation of two different zygotes in a single embryo, whereas mosaicism results from a mitotic error in a single zygote. Several other mechanisms resulting in a chimera have been discussed in the literatu...

The birth of fraternal twins is a characteristic frequently observed in callitrichids. Cytogenetic studies have demonstrated hematopoietic chimerism in marmosets with the occurrence of two cell lines 2n=46,XX/46,XY in females and males co-twins, without phenotypic changes. Amplification by PCR have also been used to verify the presence of the SRY gene in female chimaeras. Our aim was to verify ...