Recent Advances of Researchs on Blood Types in Japan

(I) Studies on blood types of human being. In the human being C, 0 and T substances have been discovered besides Q (1935) E (1935) and S blood type (secretor and nonsecretor, 1935), and as a research method of the blood types the former iso-agglutination method has been substituted by the type-specific precipitation method as the result of which the study and analysis have come to be possible of blood group substances existing in liquid form. For this purpose anti-A, anti-B, anti-o; anti-C and anti-T precipitins are always employed as tests sera. It will be natural that many new facts have been discovered as compared with the time when two kinds of anti-A (a) and anti-B (/3) serum were used. What I have to refer to besides. is that production of various immune test sera has been made possible by consideration of the individuality of animals, i. e. " serum type " and " saliva type" of animals. All animals can be classified into four kinds of a', !3', a' (3' ,. and 0' type by the type specific agglutinins in their sera and further· divided into A+ and Atype by whether or not there exists A group