Tam K, Tang I, Ho J, Yeung W, Lee C K, Ip P, Kwok J
Division of Transplantation and Immunogenetics, Department of Pathology, Queen Mary Hospital, Hong Kong SAR, China.
Hong Kong Red Cross Blood Transfusion Service, Kowloon, Hong Kong SAR, China.
Transfus Med. 2018 Aug;28(4):310-318. doi: 10.1111/tme.12494. Epub 2017 Dec 27.
Alloantibodies against human neutrophil antigens (HNA) are associated with a variety of clinical conditions. Over the past decade, the allelic and genotypic frequencies of the five HNA systems have been evaluated. Although the HNA system is less polymorphic than human leukocyte antigens (HLA), significant differences in the genotypic and allele frequencies still exist in different populations, even those living in close proximity.
To delineate HNA genotypic and allele frequencies to provide vital information on estimating the risk of HNA-associated diseases for our local population.
Using a validated, in-house-developed assay, genotyping for HNA-1, HNA-3, HLA-4 and HNA-5 was performed on 300 samples from Chinese blood donors from Hong Kong. In addition, the frequency of the HNA-2 c.843A > T allele was also determined.
The allele frequencies of HNA-1a, -1b and -1c alleles were 67·8, 31·5 and 0%, respectively, whereas the frequencies of HNA-3a and HNA-3b were 71·0 and 29·0%, respectively. The frequencies of HNA-4a and -4b alleles were 99·5 and 0·5%, respectively, and for HNA-5a and -5b, alleles were 85·2 and 14·8%, respectively. Homozygotes for the HNA-2 c.843 TT variant were absent in our population, whereas only <4% of the population were c.843AT heterozygote carriers.
This is the first study to define HNA genotype and allele frequencies using a validated modified in-house PCR-SSP method in the Hong Kong Chinese blood donor population. Our approach provides a cost-effective assay for conducting routine HNA typing and facilitates the incorporation of these assays into routine clinical service. Our results are comparable with those reported in the Guangzhou Chinese population, but the allele frequencies in our Hong Kong Chinese population are significantly different from the reported European frequencies, confirming that a geographical difference exists for HNA allele frequencies.
针对人类中性粒细胞抗原（HNA）的同种抗体与多种临床病症相关。在过去十年中，已对五个HNA系统的等位基因和基因型频率进行了评估。尽管HNA系统的多态性低于人类白细胞抗原（HLA），但在不同人群中，即使是居住在相近地区的人群，其基因型和等位基因频率仍存在显著差异。
确定HNA基因型和等位基因频率，为评估本地人群中HNA相关疾病的风险提供重要信息。
使用经过验证的内部开发检测方法，对来自香港中国献血者的300份样本进行HNA-1、HNA-3、HNA-4和HNA-5基因分型。此外，还确定了HNA-2 c.843A>T等位基因的频率。
HNA-1a、-1b和-1c等位基因的频率分别为67.8%、31.5%和0%，而HNA-3a和HNA-3b的频率分别为71.0%和29.0%。HNA-4a和-4b等位基因的频率分别为99.5%和0.5%，HNA-5a和-5b等位基因的频率分别为85.2%和14.8%。在我们的人群中不存在HNA-2 c.843TT变异的纯合子，而只有不到4%的人群是c.843AT杂合子携带者。
这是首次在香港中国献血者人群中使用经过验证的改良内部PCR-SSP方法确定HNA基因型和等位基因频率的研究。我们的方法为进行常规HNA分型提供了一种经济高效的检测方法，并有助于将这些检测方法纳入常规临床服务。我们的结果与广州中国人群中报告的结果相当，但我们香港中国人群中的等位基因频率与报告的欧洲频率有显著差异，证实HNA等位基因频率存在地域差异。
