Background: Human neutrophil antigen 3 (HNA-3) is encoded by the SLC44A2 gene. Antibodies against HNAs can cause severe, often fatal, transfusion reactions, known as transfusion-related acute lung injury, and neonatal neutropenia. We explored the 2 common HNA-3 variants in 9 ethnic populations residing in Sichuan and Yunnan provinces of China as compared to the Han population.
Methods: We genotyped for SLC44A2 (rs2288904) by polymerase chain reaction sequence-based typing among blood donors, for a total of 2206 individuals in Yunnan and 376 in Sichuan.
Results: The SLC44A2*02 allele (HNA-3b antigen) frequency varied between 0.24 and 0.33 for all 9 ethnic populations in Yunnan, including Zhuang, Derung, Hani, Lisu, Bai, Miao, Dai, Naxi, and Yi. Specifically, the Yi ethnicity did not present an unusually great SLC44A2*02 frequency at any of the 4 locations examined in Yunnan. Except of the Yi ethnicity in Sichuan (0.40), the Han ethnicity, as the majority population group, had the greatest SLC44A2*02 frequency with 0.39 in Yunnan and 0.35 in Sichuan.
Conclusion: The ethnic populations in Southwest China are not at an increased risk for anti-HNA3a compared to the Han population, with the possible exception of Yi in Sichuan. Our data, however, corroborated the known high prevalence of SLC44A2*02 in Han populations. Hence, the Han populations in Yunnan, Sichuan and elsewhere in China are at a comparatively great risk for developing HNA-3a antibodies.
Keywords: Gene polymorphism; HNA-3 antigens; PCR-SBT genotyping; TRALI.