title: Amplification refractory mutation system-PCR is essential for the detection of chimaeras with a minor allele population: a case report.
abstract: Blood chimaera is a rare but important issue for immunohaematology laboratories. Several molecular approaches, such as ABO genotyping, human leucocyte antigen (HLA) typing and DNA short tandem repeat (STR) analysis, have been used to identify chimaerism. Unfortunately, the minor allele population can be overlooked by PCR-based methods, which preferentially amplify the major allele population. A case with AweakB (AwB), demonstrating a mixed-field pattern, was sent to our laboratory for further evaluation. Direct sequencing of ABO exons 6 and 7 revealed a B101/O02 genotype. Analysis of the 12 STR loci and HLA typing did not provide any evidence of chimaerism. However, amplification refractory mutation system (ARMS)-PCR identified the minor A102 allele in addition to B101/O02. Three alleles of the chimaera were confirmed by cloning and sequencing. Thus, ARMS-PCR is essential, especially in the case of a chimaera with a minor allele population.
authors: Department of Laboratory Medicine, Chonnam National University Medical School & Chonnam National University Hwasun Hospital, Hwasun, South Korea.
authors: Eun Jeong
authors: EJ
authors: Won
authors: Hye Ryoen
authors: HR
authors: Park
authors: Tae Sung
authors: TS
authors: Park
authors: Seung Hwan
authors: SH
authors: Oh
authors: Myung Geun
authors: MG
authors: Shin
authors: Jong Hee
authors: JH
authors: Shin
authors: Soon Pal
authors: SP
authors: Suh
authors: Dong Wook
authors: DW
authors: Ryang
authors: Jong Tae
authors: JT
authors: Park
authors: Duck
authors: D
authors: Cho
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics*; D000293:Adolescent; D000483:Alleles; D002678:Chimera / Q000097:blood*; D005091:Exons / Q000235:genetics; D005260:Female; D005784:Gene Amplification; D005838:Genotype; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D016133:Polymerase Chain Reaction / Q000379:methods*
chemical_list: D000017:ABO Blood-Group System