ena-STUDY-Blood Group Serology and Transfusion-27-09-2017-08:41:38:699-51
Identification of a novel ABO subgroup weak B allele in an Iraqi family
An ABO blood group typing discrepancy found during routine serologic testing was further evaluated using molecular genetic analyzes. In the ABO gene of an Iraqi male with aberrant weak B phenotype a novel ABO B allele, characterized by a duplication based insertion was identified. Material and Methods ABO phenotypes of family members were determined by standard agglutination tests and adsorption-elution studies. ABO genotyping including regulatory regions as well as allele-specific sequencing analyzes and were carried out. ResultsThe propositus showed no serologically detectable A and B antigens on his red blood cells indicating blood group O. Anti-B was absent in the serum in reverse blood group typing. Employing adsorption/elution method weak B antigens on the erythrocytes were detected. Molecular genetic analysis identified an insertion of 27 base pairs in Exon 6 of the B101-like-allele. The recognized mutation also was present in his mother.ConclusionSince the novel allele was associated with a well described O allele in the propositus, the weak B antigens in the inherited ABO subtype phenotype may be caused by the insertion based mutation weakening the transferase activity of the encoded protein.
An ABO blood group typing discrepancy found during routine serologic testing was further evaluated using molecular genetic analyzes. In the ABO gene of an Iraqi male with aberrant weak B phenotype a novel ABO B allele, characterized by a duplication based insertion was identified. Material and Methods ABO phenotypes of family members were determined by standard agglutination tests and adsorption-elution studies. ABO genotyping including regulatory regions as well as allele-specific sequencing analyzes and were carried out. ResultsThe propositus showed no serologically detectable A and B antigens on his red blood cells indicating blood group O. Anti-B was absent in the serum in reverse blood group typing. Employing adsorption/elution method weak B antigens on the erythrocytes were detected. Molecular genetic analysis identified an insertion of 27 base pairs in Exon 6 of the B101-like-allele. The recognized mutation also was present in his mother.ConclusionSince the novel allele was associated with a well described O allele in the propositus, the weak B antigens in the inherited ABO subtype phenotype may be caused by the insertion based mutation weakening the transferase activity of the encoded protein.