Blood group serology and gene detection in patients with B(A) subgroup in Jiaozhou, Qingdao / 中国输血杂志

【Objective】 To investigate and analyze the serological and molecular biological characteristics of B(A) subgroup in a tertiary hospital in Jiaozhou, Qingdao. 【Methods】 From November 2019 to February 2023, the samples of 12 patients were suspected to be AB subgroup by microcolumn glass bead method and saline test tube method. The exons 6 and 7 of ABO gene were further amplified, sequenced and analyzed to determine the ABO allele type. 【Results】 A total of 9 cases of B(A) subgroup were detected in 26 065 patients in Jiaozhou, with a detection rate of 0.345 ‰ ( 9/26 065 ). Among the 9 cases of B(A) subgroup, 8 cases of serological reaction showed AweakB, and the gene detection was heterozygous for BA.04 gene and O gene.One case of serological reaction showed ABweak, and the gene detection was heterozygous for BA.04 gene and A gene. 【Conclusion】 Blood group serological combined with gene detection can accurately identify ABO blood group. B(A) subgroup alleles can exist in individuals with serological reaction of ABweak.

Identification and clinical transfusion of B (A) subgroup / 中国输血杂志

【Objective】 To carry out serological and molecular biological identification of B (A) subtype, and discuss the rational blood transfusion strategy. 【Methods】 Serological and direct sequencing methods were used to detect serotype and genotype of 7 cases of B (A) subtype, and cross matching was performed by saline medium and anti human globulin card to analyze the red blood cells(RBCs) transfusion strategy. 【Results】 The serology results of blood type of 7 samples were similar, with B(A)04/O01 in 3 cases, B(A)04/O02 in 2 cases and B(A)02/O01 in 2 cases. 7 cases of B (A) subtypes were matched with randomly selected blood donors of type O and B on the major side. 【Conclusion】 B(A) subtypes should be identified by genotyping techniques. Washed RBCs of type B and O can be used for B(A) blood type transfusion.

Identification for rare B(A) blood group / 临床检验杂志

Objective To investigate the serological and molecular identification of 2 rare B( A) blood groups. Methods The ABO blood groups of 2 samples from blood donors were detected by routine serological method. The genotype features was identified by PCR-sequence specific primer (PCR-SSP) and direct sequence analysis. Results The serological results for the 2 blood donors showed the characteristics of B(A) phenotype. The sample 1 was genotyped as BO2 subtype by PCR-SSP and direct sequencing showed B alleles in exon 7, presented nt640 A＞G mutation which was confirmed to be B(A)04/O02 genotype.The sample 2 was genotyped as BO1 sub-type by PCR-SSP and direct sequencing showed B alleles presented nt700 C＞G mutation in exon 7 which was confirmed to be B(A)02/O01 genotype. Conclusion The phenotype of the two samples should be B ( A ) and the genotypes should be rare B(A)04/O02 and B(A)02/O01.

Identification and molecular mechanism study of a case with B(A)02 allele / 天津医药

Objective To identify and investigate B(A)02 allele in a patient. Methods Serological tests were performed with standard serological methods in a patient with B(A)02 allele. DNA sequences of all seven exons and exon-intron boundaries of ABO gene were analyzed by polymerase chain reaction (PCR), direct DNA sequencing and sequencing after gene cloning. In order to analyze the allele, PyMOL software was used to establish 3D model of Glycosyltransferases B (GTB). Results The serological results showed the characteristics of B(A) phenotype. DNA analysis revealed that ABO gene of the individual was heterozygous of B(A)02/O01 allele. 700C>G mutation was identified in B101 allele, which resulted in the amino acid substitution P234A in GTB. Through the analysis of the 3D structure of GTB, it was speculated that the P234A replacement affected the intermolecular forces of the 234 amino acid and Met-266, thus changed the conformation of the donor-binding pocket of GTB,that made GTB capable of recognizing and tranferring the GalNac to the H antigen, which can lead to the formation of the weak A antigen on membrane of red blood cells. Conclusion The P234A replacement can affect the spatial conformation of the specific recognition region conformed by Met-266 and Ala-268 residues, which leads to the antigenicity change of the ABO blood group.

Study on B(A) phenotypes and identification of novel B(A)641 allele in chinese population / 中国输血杂志

C mutation. All 8 samples displayed the B(A) phenotype. Their real genotypes were B(A)/O. Conclusion Three B(A) alleles in the Chinese Han population were detected. Two alleles,B(A)700,B(A)640 were reported previously. One novel allele B(A)641, was first identified in this study.