Human neutrophil alloantigen genotype frequencies in Thai blood donors

Antibodies to human neutrophil antigens (HNA) can cause transfusion reactions, as well as autoimmune and neonatal neutropenia. This study is the first to report the frequencies of human neutrophil antigen genotypes in the Thai population.

Three hundred unrelated, healthy Thai blood donors at the National Blood Centre, Thai Red Cross Society, Bangkok, Thailand were typed for HNA-1a, -1b, -1c, -3a, -3b and -4a using polymerase chain reaction with sequence-specific primers. Moreover, HNA-5a genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism.

The gene frequencies of HNA-1a, -1b and -1c were 0.470, 0.530 and 0.005, respectively. The frequencies of HNA-3a and -3b were 0.490 and 0.510, respectively. Additionally, the HNA-4a+/+ and HNA-4a+/- genotype frequencies were 0.947 and 0.053, respectively. The frequencies of HNA-5a+/+, HNA-5a+/- and HNA-5a-/- genotypes were 0.641, 0.297 and 0.062, respectively. Compared with other Asian populations, Thais have higher frequencies of HNA-1b (P<0.001). On the other hand, the frequency of HNA-5a observed in Thais is lower than that reported among Koreans (P<0.001).

These findings suggest that Thais would be more susceptible to HNA-1b alloimmunisation. Furthermore, our results could establish a useful human neutrophil antigen donor file to provide more effective transfusion of blood and blood components.