MN Blood Group system in Humans

The MN blood group system is under the control of an autosomal locus found on chromosome 4, with two alleles designated LM and LN. The blood-type is due to a glycoprotein present on the surface of red blood cells, which behaves as a native antigen. Phenotypic expression at this locus is co-dominant because an individual may exhibit either one or both antigenic substances. Frequencies of the two alleles vary widely among human populations.


Table from Griffiths et al. 1996; Text material © 2017 by Steven M. Carr