Xia R W, Xun C Z, Xiang D, Zhang J M, Yang Q X, Zhao F Y, Wang C, Zhu Z Y, Li Q, Ye L Y
Blood Group Reference Laboratory, Qujing Blood Center, Qujing, China.
Shanghai Institute of Blood Transfusion, Shanghai Blood Center, Shanghai, China.
Transfus Med. 2019 Dec;29(6):460-465. doi: 10.1111/tme.12598. Epub 2019 Apr 29.
AIMS/OBJECTIVES: We aimed to analyse the molecular backgrounds and red blood cell (RBC) antigen expression of a male blood donor with Rh phenotype and his family members.
Rh deficiency phenotypes are rarely found worldwide and are characterised by the lack of Rh antigen expression on RBCs. During routine screening, we found a blood donor who seemingly lacked Rh antigens. Therefore, we recruited the donor and his family for further investigation.
RBC serotyping and antibody screening/identification were performed for each sample. A routine blood examination was also conducted. RHD, RHCE and RHAG were sequenced at the genomic DNA or RNA level. Eleven antigens or proteins associated with Rh complex were tested using flow cytometry analysis.
The proband and one of his brothers showed extremely weak D antigen and Rh expression levels but did not manifest anaemia. Most of the expressed RBC antigens of the two Rh-deficient individuals were similar to the previously reported cases but with some exceptions. Molecular analyses demonstrated homozygous expression of a novel RHAG allele, namely, c.[572G>A;707A>C], both in the proband and one of his brothers.
To our knowledge, we identified the second double-variant RHAG allele and the first one related to Rh phenotype. The novel allele was also confirmed to be heritable by family analyses.
我们旨在分析一名具有Rh血型表型的男性献血者及其家庭成员的分子背景和红细胞（RBC）抗原表达情况。
Rh缺乏表型在全球范围内很少见，其特征是红细胞上缺乏Rh抗原表达。在常规筛查过程中，我们发现一名献血者似乎缺乏Rh抗原。因此，我们招募了该献血者及其家人进行进一步调查。
对每个样本进行红细胞血清分型和抗体筛查/鉴定。同时进行常规血液检查。在基因组DNA或RNA水平对RHD、RHCE和RHAG进行测序。使用流式细胞术分析检测与Rh复合物相关的11种抗原或蛋白质。
先证者及其一个兄弟表现出极弱的D抗原和Rh表达水平，但未表现出贫血。两名Rh缺乏个体表达的大多数红细胞抗原与先前报道的病例相似，但有一些例外。分子分析表明，先证者及其一个兄弟中均存在一种新的RHAG等位基因纯合表达，即c.[572G>A;707A>C]。
据我们所知，我们鉴定出了第二个双变体RHAG等位基因，也是第一个与Rh表型相关的等位基因。通过家系分析也证实了该新等位基因具有遗传性。
