Non-ABO blood antigens affect less common human blood groups. The ABO system is the primary blood typing used in transfusions. Other rare blood types can complicate donation, with 33 major blood groups recognized by International Society of Blood Transfusion in 2012. Geography affects the distribution of antigens. These include([ISBT 3.0]):

RH, RHD results in the RhD +- status and the RHCE gene affects C/E status.

MNS, GYPA and GYPB contribute antigens

Kell, at least 34 antigens from KEL bond to XK

P, A4GALT, B3GALNT1

Lewis, determined by FUT2 and FUT3 interaction: a,b, or null antigen types

Duffy, ACKR1

Kidd, SLC14A1

Diego, SLC4A1; see rs2285644

Lutheran, BCAM has 19 antigens and has a recessive null phenotype.

Vel, SMIM1 can have a deletion causing Vel to be absent

Indian, CD44 has a,b and null types.



23andMe reports on the ABO, RH, Diego, Kell, and Kidd types. Genetics of most rare groups are still being researched.

Resources on blood systems include the ISBT, the NCBI Blood Group Antigen Gene Mutation Database.