OBJECTIVETo study the ABO allele molecular characteristics of Ael blood subgroup.

METHODSFive individuals of diagnosed as Ael blood subgroup were subjected to PCR amplify ABO alleles using four pairs of sequence-specific primers. Exon 6 and exon 7 at ABO locus of all samples were sequenced. An individual with AelB phenotype was chosen for further analysis of transcript structure of ABO gene.

RESULTSSequence analysis indicated one Ael phenotype sample with reported Ael01 allele, one Ael phenotype sample with an Ael05 allele, and two AelB and one Ael individuals did not contain referred A allele, but contain O01 or O02 allele with 261G deletion.

CONCLUSIONMolecular bases for the Ael have highly polymorphism. The mechanism responsible for the express weak A antigen of O allele with 261G deletion awaits to be elucidated.