title: [Cloning and sequence analysis of 5'untranslated region of human ABO gene].
abstract: OBJECTIVE
  To clone and investigate the polymorphism of the 5'-untranslated region (5'-UTR) of the human ABO gene, in order to provide the basis for exploring the transcriptional regulation of the human ABO histo-blood group genes.
  
  
  METHODS
  ABO phenotypes of 30 unrelated healthy blood donors were determined by serological technique, their genotypes were analyzed by sequencing the exons 6 and 7 of the ABO gene. Nearly 5 kb of the 5'-UTR of ABO gene was obtained by PCR amplification and sequencing was performed bidirectionally. Haplotypes of samples with heterozygous sites in the 5'-UTR of ABO gene were separated and analyzed after cloning.
  
  
  RESULTS
  Twenty polymorphic sites were identified in these samples where ABO genotypes were consistent with serological phenotypes. It included sixteen nucleotide sequence variations, one 8 bp deletion, one 6 bp deletion/insertion, one 36 bp insertion and one 43 bp repeats. Among them, 11 were novel polymorphic sites. Seven different haplotypes of 5'-UTR of ABO gene were defined to the cis/trans linkage of those mutations.
  
  
  CONCLUSIONS
  There were polymorphisms in the 5'-UTR of ABO gene and the nucleotide sequences near the proximal promoter were conservative.
authors.affiliation: Institute of Transfusion Medicine, Blood Center of Zhejiang Province; Key Laboratory of Blood Safety Research, Ministry of Health, Hangzhou, Zhejiang, 310006 PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Xian-guo
authors.initials: XG
authors.lastname: Xu
authors.forename: Kai-rong
authors.initials: KR
authors.lastname: Ma
authors.forename: Xiao-fei
authors.initials: XF
authors.lastname: Lan
authors.forename: Xiao-zhen
authors.initials: XZ
authors.lastname: Hong
authors.forename: Fa-ming
authors.initials: FM
authors.lastname: Zhu
authors.forename: Hang-jun
authors.initials: HJ
authors.lastname: Lv
authors.forename: Li-xing
authors.initials: LX
authors.lastname: Yan
mesh_terms: D020121:5' Untranslated Regions / Q000235:genetics*; D000017:ABO Blood-Group System / Q000235:genetics*; D003001:Cloning, Molecular; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D020121:5' Untranslated Regions; D000017:ABO Blood-Group System