Three additional examples of anti-Xga and Xg blood groups among the Japanese.

Three examples of anti-Xga identified in Japanese donors are reported. Two of these were stimulated by pregnancy, while the antibody stimulation of the other one remains unknown. All of these antibodies had the ability to bind complement. A dosage effect was observed in an anti-Xga serum. The Xga gene frequency for 529 unrelated Japanese was 0.681, similar to that for Caucasians. Tests on 125 Japanese families with 242 offspring for Xga antigen are also reported.