The blood type gene influences more than just the A and B antigens, simultaneously affecting levels of certain clotting factors and inflammatory compounds in the bloodstream. People with non-O ...

Type O: The most common blood type, with about 45% of the population having it; O-negative, the universal donor blood type, is present in only 7% of people in the U.S., while the other 38% have O ...

[1] Prevalence of rhesus D-negative blood type and the challenges of rhesus D immunoprophylaxis among obstetric population in Ethiopia. Maternal Health, Neonatology and Perinatology (2021).

The Red Cross has had to limit distribution of Type O blood, which is some of the most transfused, because of supply constraints. To encourage people to give at times when blood donations are ...