Abstract
Red blood cell Mg was measured in 351 blood donors of known HLA antigens. The level of red cell Mg is significantly lower in subjects bearing an HLA-Bw35 allele (P < 0.001). It also varies according to the HLA-Bw4 and Bw6 antigens of the subjects tested. These 2 effects seem to be independent of one another. These findings confirm the role played by genetic factors in the control of human red blood cell Mg concentrations. They are discussed in the light of the relationship between HLA groups and diseases.