title: The genetic and phenotypic basis of blood group A subtypes in Koreans.
abstract: A serological and genetic study of Korean blood donors with phenotypic group A subtypes was performed. There were 176 donors with phenotypic A subtypes identified. Exons 6 and 7 from 57 representative donors were sequenced. The A(var) allele (784 G > A) was cloned and sequenced, and a family study demonstrating its inheritance and unusual serological characteristics was performed. The A102 allele was the most frequently identified allele in phenotypically A2 (58%, 11/19) and A2B (68%, 17/25) donors. Anti-A1 was rarely present amongst A2 and A2B donors. The family study revealed that the A(var) allele was expressed as phenotype A(weak)B in A(var)/B heterozygote members, but as phenotype O in A(var)/O heterozygotes. The most frequent allele in Korean donors with the A2 phenotype differs from its Caucasian counterpart, as does the frequency of anti-A1. The A(var) allele demonstrates allelic enhancement in A(var)/B heterozygotes.
authors.affiliation: Department of Laboratory Medicine, Chonnam National University Hospital and Medical School, Gwangju, South Korea.
authors.forename: D
authors.initials: D
authors.lastname: Cho
authors.forename: M G
authors.initials: MG
authors.lastname: Shin
authors.forename: M H
authors.initials: MH
authors.lastname: Yazer
authors.forename: S J
authors.initials: SJ
authors.lastname: Kee
authors.forename: J H
authors.initials: JH
authors.lastname: Shin
authors.forename: S P
authors.initials: SP
authors.lastname: Suh
authors.forename: M J
authors.initials: MJ
authors.lastname: Jeon
authors.forename: J W
authors.initials: JW
authors.lastname: Song
authors.forename: C S
authors.initials: CS
authors.lastname: Ki
authors.forename: D W
authors.initials: DW
authors.lastname: Ryang
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics*; D000483:Alleles; D001782:Blood Donors; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D040582:Inheritance Patterns; D007723:Korea; D010375:Pedigree; D010641:Phenotype; D017422:Sequence Analysis, DNA
chemical_list: D000017:ABO Blood-Group System