Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, South Korea.
Blood Transfus. 2021 Jul 9;19(4):327-334. doi: 10.2450/2020.0128-20. Epub 2020 Oct 9.
The molecular basis of RhD blood groups differs with race/ethnicity. This study aimed to investigate the molecular basis of serological weak D phenotypes and RhD typing discrepancies in the Korean population.
The RhD status of 188,852 Korean patients was initially determined using the automated microplate method and manual tile method. In case of no agglutination, weak D testing was further performed using the tube and gel methods. Serologically D-negative samples with C+ and/or E+ were tested using polymerase chain reaction-sequence specific primers for four RHD targets and/or exon 9 sequencing. Samples showing a serological weak D phenotype or an RhD typing discrepancy were subjected to full RHD gene sequencing.
Of the 32 samples showing a serological weak D phenotype and 191 samples showing a serologically D-negative phenotype with C+ and/or E+, 23 and 50 were genotyped, respectively. Among the weak D samples, the most common alleles were RHD15 (n=6), RHD13.01 (n=4), and RHD01W.25 (n=4), and no variant was found in two samples. RHD01EL.01 (n=26) accounted for more than half of the D-negative samples. Of the seven samples that were typed as D-positive using the automated microplate method but showed weak reactivity using the tile method, four were genotyped, and the results were as follows: RHD01W.33 (n=2), RHD01W.43 (n=1), and no variant found (n=1).
In our cohort, various D variant alleles including RHD15 were identified; however, RHD01W.1, RHD01W.2, RHD01W.3, RHD09.03.01, and RHD09.04, accounting for more than 95% of Caucasians with a serological weak D phenotype, were not found. Our study reaffirms that the distribution of D variant alleles differs between East Asians and Caucasians. Our findings also indicate that some D variants including RHD01W.33 and RHD01W.43 are at risk of being mistyped as D-positive by a highly sensitive RhD typing method such as an automated microplate method.
RhD 血型的分子基础因种族/民族而异。本研究旨在探讨韩国人群中血清学弱 D 表型和 RhD 分型差异的分子基础。
使用自动微孔板法和手动平板法初步确定 188,852 例韩国患者的 RhD 状态。在无凝集的情况下，进一步使用试管和凝胶法进行弱 D 检测。用聚合酶链反应-序列特异性引物对四个 RHD 靶标和/或外显子 9 测序检测 C+和/或 E+的血清学阴性 D 样本。对表现为血清学弱 D 表型或 RhD 分型差异的样本进行完整的 RHD 基因测序。
32 例表现为血清学弱 D 表型的样本和 191 例表现为 C+和/或 E+血清学阴性 D 表型的样本分别进行了 23 例和 50 例基因分型。在弱 D 样本中，最常见的等位基因为 RHD15(n=6)、RHD13.01(n=4)和 RHD01W.25(n=4)，两个样本未发现变异。RHD01EL.01(n=26)占阴性样本的一半以上。在使用自动微孔板法分型为 D 阳性但使用平板法反应较弱的 7 例样本中，有 4 例进行了基因分型，结果如下：RHD01W.33(n=2)、RHD01W.43(n=1)和未发现变异(n=1)。
在本队列中，鉴定了包括 RHD15 在内的各种 D 变异等位基因；然而，在血清学弱 D 表型的高加索人中占 95%以上的 RHD01W.1、RHD01W.2、RHD01W.3、RHD09.03.01 和 RHD09.04 并未发现。本研究再次证实，东亚人和高加索人之间 D 变异等位基因的分布不同。我们的研究结果还表明，一些 D 变异，包括 RHD01W.33 和 RHD01W.43，可能会被自动微孔板法等高度敏感的 RhD 分型方法误判为 D 阳性。
