title: An intron mutation in the ACVRL1 may be associated with a transcriptional regulation defect in a Chinese family with hereditary hemorrhagic telangiectasia.
abstract: OBJECTIVE
  To identify a novel pathogenic gene mutation present in a Chinese family with hereditary hemorrhagic telangiectasia (HHT) and to determine if an intron mutation may influence the transcriptional activity of the ACVRL1 gene.
  
  
  METHODS
  HHT family members were ascertained following the presentation of proband and involved subjects. All family members (n = 5) and 113 healthy individuals were genotyped for the variant in intron 6 c.772+27G>C of ACVRL1 gene. The genomic structure of ACVRL1 in affected HHT patients and healthy individuals was determined by long range PCR and sequencing. The expression of ACVRL1 mRNA and protein in patients with HHT was evaluated using real-time polymerase chain reaction and immunoblot analysis. Luciferase activity assay and electrophoretic mobility shift assay (EMSA) were performed to uncover the mechanism of intron-related transcriptional regulation.
  
  
  RESULTS
  Only one novel mutation in intron 6 (c.772+27G>C) of ACVRL1 gene, no other mutation, abnormal splice, gross genomic deletion or rearrangement was found in this HHT2 family. Compared with healthy individuals, ACVRL1 mRNA and protein were significantly decreased in affected HHT2 individuals. Luciferase activity assay demonstrated that the transcriptional activity of the mutated ACVRL1 was significantly lower than that of the wild-type of intron 6; EMSA results showed that intron 6 c.772+27G>C mutation was able to inhibit the binding of transcriptional factor Sp1.
  
  
  CONCLUSIONS
  A novel intron mutation in ACVRL1 gene is associated with familial HHT2. The mechanisms may be involved in the down-regulation of ACVRL1 gene transcription.
authors: Division of Hematology, Institution of molecular hematology, The Second Xiang-Ya Hospital, Central South University, Changsha, Hunan, People's Republic of China.
authors: Qian
authors: Q
authors: Yu
authors: Xiao-Hui
authors: XH
authors: Shen
authors: Ying
authors: Y
authors: Li
authors: Rui-Juan
authors: RJ
authors: Li
authors: Ji
authors: J
authors: Li
authors: Yun-Ya
authors: YY
authors: Luo
authors: Su-Fang
authors: SF
authors: Liu
authors: Ming-Yang
authors: MY
authors: Deng
authors: Min-Fei
authors: MF
authors: Pei
authors: Guang-Sen
authors: GS
authors: Zhang
mesh_terms: D030301:Activin Receptors, Type II / Q000235:genetics*; D000328:Adult; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D044466:Asian People / Q000235:genetics*; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002675:Child, Preschool; D002681:China; D016384:Consensus Sequence / Q000235:genetics; D015536:Down-Regulation / Q000235:genetics; D000071063:Endoglin; D005190:Family; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D020022:Genetic Predisposition to Disease; D006801:Humans; D007438:Introns / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D010375:Pedigree; D011485:Protein Binding / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D013683:Telangiectasia, Hereditary Hemorrhagic / Q000235:genetics*; D014158:Transcription, Genetic; D015854:Up-Regulation / Q000235:genetics
chemical_list: D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C425364:ACVRL1 protein, human; D030301:Activin Receptors, Type II