A Clinical and Cytogenetical Study of Three Patients With Male Phenotype and Apparent Xx Sex Chromosome Constitution

Three male patients with testicular dysgenesis are described. In all three patients testicular histology showed advanced tubular sclerosis and Leydig cell hyperplasia. Two were of short stature and none had gynaecomastia. They were all euthyroid with normal PBI, but two of them showed decreased thyroid uptake of 131 I and a decreased »TSH reserve«. In all three cases cells from several tissues had 46 chromosomes and an XX sex chromosome constitution. In one mosaicism was indicated by the presence of a very small proportion of cells with 47 chromosomes. Some of these cells seemed to contain three X chromosomes whereas the others had two X chromosomes and possibly a Y. No evidence of mosaicism was found in the other two. There were no signs of structural chromosome abnormalities.