A novel B_var allele (547 G>A) demonstrates differential expression depending on the co‐inherited ABO allele

Abstract

B(var) allele is subject to differential expression, depending on the co-inherited ABO allele.

The M142T Mutation Causes B3 Phenotype: Three Cases and anin vitroExpression Study

“…Among the B 3 alleles, the B306 allele has also been found in some Korean blood donors [6]. This allele demonstrated …”

“…1 The coding and flanking intronic sequences of ABO exons 6 and 7 of the neonate and 4 other family members were amplified, cloned, sequenced, and analyzed, as described previously [6,[14][15][16] antigen produced by the control B101 transfects (Fig. 3C).…”

“…This gene contains 7 exons, of which the last 2 (6 and 7) comprise nearly 80% of the coding sequence of the gene and encode the catalytic domain [1,2]. The genetic underpinnings of several B subtype phenotypes have been reported [3][4][5][6][7][8][9][10][11][12]. Although it is considerably rarely observed in Korea and probably the entire Asia, the B3 phenotype is the most common B subtype phenotype [6,7].…”

“…The genetic underpinnings of several B subtype phenotypes have been reported [3][4][5][6][7][8][9][10][11][12]. Although it is considerably rarely observed in Korea and probably the entire Asia, the B3 phenotype is the most common B subtype phenotype [6,7]. B 3 alleles are heterogeneous and contain single nucleotide polymorphisms (SNPs) scattered throughout both the coding and intronic DNA sequences; however, some individuals with the B3 phenotype had no unexpected SNPs relative to the B101 allele [8].…”

The p.R168Q mutation is associated with the Bw phenotype and a predicted decrease in the stability of the resulting ABO glycosyltransferase

“…, the natural expression of the new ABO*Bw allele is the normal B phenotype as demonstrated in Individual [I‐1]; when it is inherited with a normal ABO*A allele, a B 3 or B w phenotype is produced that is consistent with the phenomenon known as “allelic competition” [II‐1 and III‐1]. Other alleles ( ABO*Aw14 and ABO*B306 ) that demonstrate allelic competition have been reported in Koreans: An ABO*Aw14 gene was expressed as A w in an ABO*Aw14/ABO*O01 heterozygote, but no A antigen was detected in an ABO*Aw14/ABO*B101 heterozygote by serologic testing methods including adsorption and elution; a ABO*B306 gene was expressed as a normal B phenotype in ABO*B306/ABO*O01 and ABO*B306/ABO*O02 heterozygotes, but as an A 1 B 3 phenotype in an ABO*A102/ABO*B306 heterozygote . Although the neonate and her father have the same ABO*A102/ABO*Bw genotype, as shown in Fig.…”