Chromosome measurements on an XXp+ male.

Measurements carried out on an XX male show that there is a significant difference between the lengths of the short arm of the 2 X chromosomes of this patient and that the short arm of the longer X is also significantly different from that of the X chromosomes derived from normal individuals. The difference lies specifically in the size of the terminal band of the short arm. These results are consistent with the X-Y interchange hypothesis of Ferguson-Smith.