Common RBC antigens in O type Tunisian blood donors and their importance in alloimmunization

Abstract

Abstract Background The presence of some red blood cell (RBC) antigens may affect the preference for using type O blood in emergency situations because they may induce complex or multiple alloimmunization in special circumstances. Methods A subgroup of 77 type O blood Tunisian donors were genotyped for 19 common blood alleles using the single specific primer–polymerase chain reaction method. The statistical analysis was done using HaploView software. Results The study showed the dominance of the alleles RH*5, KEL*2, FY*2, and CO*1 and the absence of the homozygous state of the KEL*1 and CO*2 alleles. Furthermore, a complete linkage disequilibrium between the RH*2/RH*4 and RH*3/RH*5 loci and the FY*Null/FY*Exp and FY*A/FY*B loci was detected. Additionally, it seems that sensitization to MNS:3, FY:1, and RH:3 may constitute a potential factor for alloimmunization after transfusion with O blood type units: the probabilities of simple alloimmunizations are 24.5 per 100, 18.5 per 100, and 18 per 100, respectively. Multiple alloimmunization against RH:1;KEL:1 or RH:1;KEL:1;RH:3 phenotypes may occur, with probabilities of 7 per 1000 and 2 per 1000, respectively. Conclusion Some O-type RBC units may contain blood with very immunogenic phenotypes, the use of which in an emergency requires great caution because it can be a step towards subsequent alloimmunization.