Dispermic chimera associated with dysgerminoma

A 12-year-old female patient (Miss E.Y.) suffering from abdominal tumor was proved to be a dispermic or generalized chimera. Ninety-two percent of her red cells were group A1, the first locus of phosphoglucomutase (PGM1) 1A, 6-phosphogluconate dehydrogenase (PGD) AC and 8% of them were group B, PGM1 1A-2A, PGD A. Ninety cells out of one hundred and ten cultured lymphocytes were normal 46 XY and 20 cells were normal 46 XX. She secreted B and H substances at normal secretor range and a small amount of A substance in her saliva. The A-transferase level found in her serum was about 40% of those of group A1 individuals. The B-transferase level was in the normal range. Her hairs had B antigen and PGM1 phenotype of their root cells was 1A-2A. The cells of hair root were X chromatin-positive and Y body-negative. Her nails had lesser A antigen and potent B antigen. Major epithelial cells (approximately 75%) of her buccal mucosa expressed B antigen and minor cells expressed A antigen. The proportion of the X chromatin-positive buccal cells (15%) was lower than those in normal females (20-25%) and that of Y body-positive buccal cells (10%) was higher than those in normal females (0-3%). The surgically resected abdominal tumor was her right uterine adnexa with malignant transformation, the histological diagnosis of which was dysgerminoma. The tumor cell nest and the epithelial cells of ductal structure expressed A antigen, whereas the endothelial cells of blood vessels expressed B antigen. These findings showed that the proband's body cells arose from the two cell lines, one carrying A1 gene had normal 46 XY male karyotype and another carrying B gene had normal 46 XX female karyotype, and suggested that her right gonad which was contributed by the former cell line had a malignancy in the presence of Y chromosome.