Tokyo researchers scrutinized the medical statements of nearly 900 patients who visited either of the two emergency critical medical centers located in Japan. These medical reports belonged to the period from 2013 to 2016. The researchers observed that the statements pertain to the patients suffering from the severe trauma. The severe medical trauma is fatal and is defined to be the sole cause of permanent disability or to kill someone.

The reports were then subjected to the groupism based on the blood types. It was observed that out of all the case studies, twenty-eight percent of the blood type O individuals lost their lives, in spite of being subjected to the medical treatment. This was in lieu of the other blood type individuals where the death percent was merely eleven percent.

Blood types determine the antigen combinations that mask our red blood corpuscles. It is this antigen combination, which attributes us with a unique blood type. Currently, the no. of known antigens is six hundred. The antigens are genetic and are inherited from our parents. The antigenic combinations bifurcate the humans into more than thirty-five blood groups. The major blood groupings are the ABO blood type and the Rhesus group. Out of the sixty-one different antigens known within the Rhesus blood groups, the D antigen is the essential antigen. It is the presence or the absence of the d antigens that determine the positive or the negative factor of the human blood group systems.

The study, however, fails to justify the reason behind the death of the most likely Blood Type O individuals. Yet, the O Blood Type individuals are known to bear a lower protein level to clot the blood.