[Whole exome sequencing and pedigree analysis for a case with an ABw03 subtype].

OBJECTIVE

To explore the molecular basis for a blood donor with an ABO subtype.

METHODS

The proband and his family members were subjected to serological analysis. Their genotypes were determined by real-time PCR and sequencing of the coding regions of ABO gene.

RESULTS

The proband was determined as an ABw subtype. By sequencing analysis, the proband was typed as A102/BW03. Compared with ABO*B.01, the proband was found to harbor a 721C>T variant (ABO*BW.03 allele) in exon 7 of the ABO gene, which caused substitution of Arginine at position 241 by Tryptophan resulting in a ABW phenotype. The blood type of the proband's sister was similar to that of the proband. The maternal serological pattern was B type, and the result of sequencing suggested that the genotype fit with B101/Bw03.

CONCLUSION

The 721C>T in the exon 7 of the ABO glycosyltransferase gene probably underlies the Bw03 phenotype. The ABO*Bw.03 variant of the proband and his sister were inherited from their mother.