First report of a patient with a mixoploidy 47,XXX/94,XXXXXX.

We present a 16 years old female with a chromosomal mixoploidy and multiple phenotypic anomalies. Peripheral blood G-band karyotype was 47,XXX and her skin fibroblast karyotype revealed a mosaic with a 47,XXX cell line in 88% of metaphases and a 94,XXXXXX cell line in 12% of metaphases, consistent with a hypertetraploidy. The most prominent clinical signs were: short stature, left upper limb asymmetry, senile-like appearance, generalized hypertrichosis, and small hands and feet. Radiological examination showed bone dysplasia. The result of molecular studies demonstrated that the patient inherited the two X chromosomes from the mother and one from the father, indicating that her 47,XXX trisomy resulted from an oogenesis error in the first meiotic division. The 94,XXXXXX cell line was likely the result of a cytokinesis error. To our knowledge, this is the first documented patient with a trisomy and a hypertetraploidy.