Figure 3.

In situ hybridization with double labeling for X and Y chromosome–specific sequences of PBMCs from male patients with scleroderma (above) and scleroderma/myositis overlap (below). A cell with 2 X chromosomes (green) is seen among male cells that contain both a Y chromosome (red) and an X chromosome (green) in each of the patients. (In the top panel, the X and Y signals are superimposed in the cell adjacent to the cell with 2 X signals.) The only known sources of female cells in the patients were their mothers. Neither patient had a history of blood transfusion or was a twin. ×100.