title: [The molecular genetics basis for ABw07 phenotype of ABO subtype].
abstract: OBJECTIVE
  To analyze the molecular genetic basis for a case of ABw07 phenotype of ABO subtype.
  
  
  METHODS
  The ABO group antigens on red blood cells of the proband were identified by monoclonal antibodies and the ABO antibody in serum was detected by the standard A, B and O cells. The exons 6 and 7 of the ABO gene was amplified by PCR and the PCR product was sequenced directly after enzyme digestion. The amplified product was also cloned by TOPO TA cloning sequencing kit to split the two alleles apart, chosen colonies were sequenced bidirectionally. The samples of the parents and one sister of the proband were collected, then the blood group serological test and sequence analysis for exon 6 to 7 of ABO gene were performed.
  
  
  RESULTS
  Both A and B antigen were detected on red blood cells of the proband and there was anti-B antibody in the serum. There was no 261G deletion. And the 297A/G, 467C/T, 526C/G, 657C/T, 703G/A, 796C/A, 803G/C, 930G/A, 1055G/A and 1096A/G loci were heterozygotes by direct DNA sequencing, which can be assigned for A102Bw07 genotype. After cloning and sequencing, two alleles of A102 and Bw07 were obtained. The Bw07 has one nucleotide change of G to A at nucleotide 1055 compared with B101, which results in an amino acid change from Arg to Gln at nucleotide 352. The Bw07 in the proband was inherited from his mother, and the serological characteristic of the ABO blood group and the sequence of exons 6 and 7 of the mother were the same as that of the proband.
  
  
  CONCLUSIONS
  The G to A at nucleotide 1055 of alpha -1, 3 galactosyltransferase gene (B gene) can result in BW7 phenotype, with anti-B antibody in serum.
authors.affiliation: The Medical College, Zhejiang University, Hangzhou, Zhejiang 310058, P. R. China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.forename: Yaling
authors.initials: Y
authors.lastname: Wu
authors.forename: Xiaotao
authors.initials: X
authors.lastname: Li
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: Hong
authors.forename: Xianguo
authors.initials: X
authors.lastname: Xu
authors.forename: Faming
authors.initials: F
authors.lastname: Zhu
mesh_terms: D000017:ABO Blood-Group System / Q000235:genetics*; D000483:Alleles; D001483:Base Sequence; D001788:Blood Grouping and Crossmatching; D003001:Cloning, Molecular; D005260:Female; D006579:Heterozygote; D006801:Humans; D008297:Male; D008967:Molecular Biology; D010641:Phenotype; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D000017:ABO Blood-Group System