等候肾移植患者中RHD阴性血液样品的基因分型及意义

Genotyping of RhD-negative blood samples diagnosed by serological tests from patients waiting for kidney transplantation

目的探讨等候肾移植患者中RHD阴性血型基因血清学与分子生物学的差异。方法收集2006年1月~2016年1月广州市各器官移植中心等候肾移植的患者中经血清学检测为Rh D阴性的血样103例,采用分子生物学方法(定量PCR-测序技术)进行RHD基因分型。血清学与分子生物学两种方法对Rh D假阴性检出率行χ2检验。结果 103例血样中,Rh D真阴性(即10个外显子全部缺失)56例(54.5%),Rh D假阴性(即Rh D阳性,但是10个外显子中有部分缺失、重复、错义突变)47例(45.6%)。在47例Rh D假阴性中,弱D(weak D)1例(2.1%)、部分D(partial D)13例(27.7%)、放散D(D-elution)33例(70.2%)。血清学与分子生物学对Rh D阴性识别的差异呈统计学显著性(P<0.05)。结论 103例血清学检测出的Rh D阴性中有45.6%通过分子生物学方法检测实际为Rh D阳性变异体,说明血清学技术对识别Rh D阴性呈较高错误率。利用分子生物学技术进行受者和供者RHD血型基因分型,对于精确肾移植配型具有重要的临床意义。

Objective To compare the accuracy of serological and molecular approaches to identification of RhD-negative patients waiting for kidney transplantation. Methods A total of 103 RhD-negative blood samples by serological test were collected from patients waiting for kidney transplantation between January, 2006 and January, 2016. Quantitative PCR and sequencing were used to verify the results of RHD genotyping, and the false negative rates of the serological and molecular methods for RhD genotyping were compared. Results Among the 103 blood samples, true RhD negativity （with all the 10 exons missing） was found in 56 samples （54.5%）, and false RhD negativity （RhD positivity with loss, repetition, or missense mutation in the 10 exons） in 47 samples （45.6%）. In the 47 false RhD-negative cases, weak D was detected in 1 case （2.1%）, partial D in 13 cases （27.7%）, and D-elution in 33 cases （70.2%）. The detection rates of RhD negativity differed significantly between the serological and molecular methods （P〈0.05）. Conclusion Serological test is associated with a high false negative rate in detecting RhD blood group, and the use of the molecular approach has important clinical significance in accurate RhD genotyping for patients waiting for renal transplantation.