Blood type without the Gregory (Gya) antigen, a high frequency antigen, is extremely rare. A woman showing Gy (a-) received anti-Gya antibody during pregnancy. Two infants born to the woman developed hemolytic disease. There has been no previous report of hemolytic disease in infants born to mothers with anti-Gya antibody. In the present case, the results of a positive direct anti-globulin test on cord blood cells differed from those reported previously. Furthermore, there have been no previous reports describing the IgG subclass in Gy (a-) subjects (IgG1, and IgG4 in the present case). During perinatal care of a pregnant woman with anti-Gya antibody, it is important to provide compatible blood; the present case suggests that transfusion management in these women should consider the possibility of hemolytic disease occurring in the newborn.
