It is possible that during its long history, smallpox may have altered the frequency of the ABO blood types by selecting against the A allele.

Question

Quizplus · Accepted Answer

Historical evidence and scientific studies suggest that certain infectious diseases, including smallpox, could have influenced the frequency of ABO blood types in human populations by exerting selective pressure, potentially selecting against individuals with the A allele due to differences in susceptibility or severity of disease.

It Is Possible That During Its Long History, Smallpox May