title: Genetical study of mutation in maternal-fetal ABO incompatibility.
abstract: This study looked into a family involving a rare mother-child ABO blood type inconsistency and explored its genetic and molecular basis. In the family, the mother had type AB blood and the father was blood type B and they gave birth to a baby of blood type O. Their blood types were phenotypically identified by using different techniques, including micro-column gel test, immune inhibition test, absorption and elution tests. The sequences of all 7 exons of ABO allele from the core family members were determined by using PCR and clone-based sequencing. The loci of mutated gene were compared against normal human genes. The result showed that the mother's erythrocytes were agglutinable with monoclonal anti-A antibody (2+) and had agglutination reaction with anti-B antibody (4+). The mother's serum registered agglutination action with standard blood type A cells. The findings showed an ABO inconsistency. When domestic antibodies were used, the mother's erythrocytes yielded agglutination reaction with humanized anti-B serum (4+) and anti-B monoclonal antibody but were non-agglutinable with humanized anti-A serum and anti-A monoclonal antibody. Upon absorption and elution, the titer of anit-A antibody was 128 both before and after the absorption test, with no significant difference found between pre- and post-absorption values. Our results confirmed that the mother's allelic gene was type B and contained type A. The father's blood type was type B, and son's blood type was type O. Clone-based sequencing revealed that the mother carried a heterozygous gene of B101.01 (ntA640→G)/O01, which contained an M214→V mutation that could express a weak expression of antigen A, resulting in blood type AB. However, their son did not have the M214→V mutation, which yielded a false ABO-inconsistency between him and his mother. We were led to conclude that type B gene with a M214→V mutation can encode both antigen B and weak antigen B that can lead to false ABO-inconsistencies.
authors: Department of Blood Transfusion, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors: Zhong-Qing
authors: ZQ
authors: Yu
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Feng-Lan
authors: FL
authors: Hu
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Qiong
authors: Q
authors: Cheng
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Jian-Hua
authors: JH
authors: Hao
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Jian-Hua
authors: JH
authors: Zhang
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Xue-Na
authors: XN
authors: Lin
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Bao
authors: B
authors: Zheng
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Ping-Ping
authors: PP
authors: Fa
authors: Department of Blood Transfusion, Shenzhen Nan Shan Hospital, Shenzhen, 518052, China.
authors: Su-Yan
authors: SY
authors: Yu
authors: Department of Blood Transfusion, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China. xhhlh@126.com.
authors: Li-Hua
authors: LH
authors: Hu
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics* / Q000276:immunology; D000328:Adult; D001483:Base Sequence; D017931:DNA Primers; D005260:Female; D006801:Humans; D008431:Maternal-Fetal Exchange; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid
chemical_list: D000017:ABO Blood-Group System; D017931:DNA Primers