[Identification of a novel Bx allele of the ABO blood group]

To identify a novel Bx13 allele.

Serological characteristics was determined with standard serological methods. All of the seven exons and flanking regions of the ABO gene were analyzed with PCR and direct sequencing. The amplicon of exon 7 was also cloned and sequenced.

The individual was determined as with a rare Bx phenotype by serological tests. Direct DNA sequencing showed that the individual was heterozygous for the B/O01 allele, while there was a novel 893C>T mutation in the B101 allele, which has led to an amino acid substitution Ala298Val in the α,3-D-galactosyl-transferase. The mutation was not found among 100 randomly selected blood donors.

A novel Bx13 allele has been identified. Substitution of amino acid in the conserved region of the enzyme may reduce the activity of α,3-D-galactosyl-transferase.