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Start free with EleplanTetragametic chimerism syndrome
ORPHA:199310Malformation syndrome
Also called 46,XX/46,XY chimerism
What it is
A rare, sex chromosome disorder of sex development characterized by the two different haploid sets of maternal and paternal chromosomes and variable phenotype - from normal male or female genitalia, to different degrees of ambiguous genitalia, and often infertility. Also, in the cases of monochorionic dizygotic twins, it can be confined to blood of both twins.
Key facts
- Age of onset
- Infancy, Neonatal
- Inheritance
- Not applicable, Unknown
- Classified as
- Malformation syndrome
Signs and symptoms
Very common80–99%
16- Abnormal cellular immune system morphology
- Abnormality of multiple cell lineages in the bone marrow
- Abnormality of the ovary
- Abnormality of the scrotum
- Abnormal testis morphology
- Ambiguous genitalia
- Bifid scrotum
- Blood group antigen abnormality
- Clitoral hypertrophy
- Cryptorchidism
- Gonadal dysgenesis with female appearance, male
- Hypopigmented skin patches
- Micropenis
- Ovotestis
- Perineal hypospadias
- True hermaphroditism
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
ICD-10 codes
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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