ABSTRACT
Objective To study the molecular genetic background of Bel subtype at ABO blood group.Methods Three samples and fifteen samples were diagnosed as Bel subgroup and normal control samples by serological test,respectively.The extracted DNA was genotyped by sequence specific primer- polymerase chain reaction foilowed by sequencing for Exon6 and exon7 at ABO locus and clones were sequenced.Results A novel Bel variant allele(GenBank EF117687) was identified in a Bel individual.The Bel allele was different from the regular B101 allele by single 952G>A missense mutation in exon7.resulting in an amino acid subsfitution of Val for Met at 318 locus.No mutations were detected in the fifteen control samples and the other two Bel allele samples.Conclusions The mutation position was fimt found to lie on coding region of ABO gene behind nucleotide 930.The mutation of G952A in the al,3 galactosyhransferase gene may be one of the molecular genetic basis of Bel ohenotype.