Molecular analysis of an individual with CisAB phenotype
10.3760/cma.j.issn.1003-9406.2020.01.019
- VernacularTitle: 一例ABO亚型CisAB个体的分子遗传学分析
- Author:
Jun LI
1
;
Liying CAO
;
Jinyou HOU
;
Hongrui ZOU
;
Hui ZHANG
;
Xiumei ZHANG
Author Information
1. Department of Blood Transfusion, Kailuan General Hospital, Tangshan, Hebei 063000, China
- Publication Type:Clinical Trail
- Keywords:
ABO blood group;
CisAB subtype;
Sequence analysis;
Variation
- From:
Chinese Journal of Medical Genetics
2020;37(1):71-74
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the molecular basis for an individual with ABO subtype.
Methods:The ABO phenotype of the proband was determined by convention serological testing. Exons 6 and 7 of the ABO gene were subjected to PCR amplification and bi-directional Sanger sequencing. Haplotypes for exons 6 and 7 of the proband was determined using an ABO haplotype-specific amplification and sequencing technique.
Results:Red blood cells of the proband showed a 4+ agglutination strength with anti-A or anti-H, no agglutination reaction with anti-A1, and a 3+ agglutination strength with anti-B. His serum had no reaction with standard A cells, O cells or self cells, but was weakly reactive with B cells at 4℃. The proband was assigned as an ABO subtype based on his serological features. Bi-directional sequencing of the ABO gene revealed heterozygosity of 261 G/del, 297AG, 526CG, 657CT, 703GA, 803GC and 930GA, and homozygosity of 796CC in the proband. Haplotype-specific amplification and sequencing showed that one of his alleles was ABO*O.01.01, and another contained a c. 796A>C variation compared with the ABO*B.01 allele, which led to replacement of methionine by leucine at position 266. Searching the ABO allele database of International Society of Blood Transfusion suggested the variation to be a novel one.
Conclusion:The c. 796A>C variation in the ABO*B.01 allele probably underlies the CisAB subtype. Accurate identification of the ABO subtype requires combined use of serological method and genetic testing.
