c The ultrasound echoic level of both gonads was homogeneous. The precise position of the external urethral opening was normal. Laparoscopy demonstrated that the vas deferens and gonadal veins flowed normally into the bilateral inguinal rings, and ovaries and a uterus were not detected (right). b On operation, epididymes were identified macroscopically, but the tunica albuginea of the testis was absent bilaterally (left). a On examination, the patient showed cryptorchidism (left), hypospadias (right), and anterior scrotum (right). After receiving approval from the Ethics Review Board for Human Genome Studies at Fujita Health University and written informed consent from the parents to participate in our study, genetic diagnosis was performed.Ĭlinical findings of the patient. The XY/XX ratio in buccal cells (17%) was lower than that in peripheral blood cells (87%). To analyze the XX/XY ratio further, we performed fluorescence in situ hybridization (FISH) analysis on interphase nuclei from the patient’s buccal mucosal cells with specific probes for chromosomes X and Y by AneuVysion Assay Kit (Abbott, Tokyo, Japan). G-banding from peripheral blood cells of the patient showed 46,XY/46,XX. The parents were recommended to undergo genetic counseling regarding detailed genetic analysis as well as recurrence risk. Macro- and microscopically, the patient had ambiguous external genitalia, male-type internal genitalia (epididymis), and bilateral testes (Fig. The patient’s toy preference was wheeled vehicles and superheroes.

His growth milestone at 1 year was normal. Abdominal magnetic resonance imaging displayed no uterus or ovaries. His father was 43 years old and mother was 31 years old. The pregnancy was not a result of in vitro fertilization treatment. The patient was born from healthy parents at an affiliated hospital as a boy with ambiguous genitalia, hypospadias cryptorchidism, and an anterior scrotum (Fig. In this report, we present a case of a parthenogenic chimera with a karyotype of XX/XY, together with a literature review. Therefore, genotyping of XX/XY chimeras is important not only to clarify its developmental mechanism but also for diagnosis and treatment, as such patients occasionally present with fertility problems. Whereas tetragametic chimeras are known as the most common subtype of XX/XY chimeras, which are derived from the simple fusion of two different zygotes, parthenogenetic chimeras and androgenetic chimeras undergo endoreplication of one of the gametic genomes. The XX/XY chimera is classified into some subtypes tetragametic chimeras, parthenogenetic chimeras, androgenetic chimeras and sesquizygotic twinning chimera. Chimeras are thought to result from a defect in the processes near the time of fertilization. The XX/XY chimera manifests variable genital phenotypes, ranging from normal male or female genitalia to different degrees of ambiguous genitalia. Although the first case was described in 1962, its incidence is still unknown. Sex-chromosome discordant chimerism in humans (XX/XY chimerism) is a rare chromosomal abnormality. If (slot) slot.addService(googletag.A chimera is defined as the fusion product of two different zygotes in a single embryo, whereas a mosaic results from a mitotic error in a single zygote. (function (a, d, o, r, i, c, u, p, w, m) Woman finds out she is her daughter's mother - and uncle - The Jerusalem Post

Genetic chimera