title: Novel collagen VI mutations identified in Chinese patients with Ullrich congenital muscular dystrophy.
abstract: BACKGROUND
  We determined the clinical and molecular genetic characteristics of 8 Chinese patients with Ullrich congenital muscular dystrophy (UCMD).
  
  
  METHODS
  Clinical data of probands were collected and muscle biopsies of patients were analyzed. Exons of COL6A1, COL6A2 and COL6A3 were analyzed by direct sequencing. Mutations in COL6A1, COL6A2 and COL6A3 were identified in 8 patients.
  
  
  RESULTS
  Among these mutations, 5 were novel [three in the triple helical domain (THD) and 2 in the second C-terminal (C2) domain]. We also identified five known missense or in-frame deletion mutations in THD and C domains. Immunohistochemical studies on muscle biopsies from patients showed reduced level of collagen VI at the muscle basement membrane and mis-localization of the protein in interstitial and perivascular regions.
  
  
  CONCLUSIONS
  The novel mutations we identified underscore the importance of THD and C2 domains in the assembly and function of collagen VI, thereby providing useful information for the genetic counseling of UCMD patients.
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China.
authors.forename: Yan-Zhi
authors.initials: YZ
authors.lastname: Zhang
authors.forename: Dan-Hua
authors.initials: DH
authors.lastname: Zhao
authors.forename: Hai-Po
authors.initials: HP
authors.lastname: Yang
authors.forename: Ai-Jie
authors.initials: AJ
authors.lastname: Liu
authors.forename: Xing-Zhi
authors.initials: XZ
authors.lastname: Chang
authors.forename: Dao-Jun
authors.initials: DJ
authors.lastname: Hong
authors.forename: Carsten
authors.initials: C
authors.lastname: Bonnemann
authors.forename: Yun
authors.initials: Y
authors.lastname: Yuan
authors.forename: Xi-Ru
authors.initials: XR
authors.lastname: Wu
authors.forename: Hui
authors.initials: H
authors.lastname: Xiong
mesh_terms: D000293:Adolescent; D000483:Alleles; D019943:Amino Acid Substitution; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D002681:China; D003062:Codon; D024142:Collagen Type VI / Q000235:genetics*; D005260:Female; D016368:Frameshift Mutation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009136:Muscular Dystrophies / Q000175:diagnosis / Q000235:genetics*; D009154:Mutation; D020125:Mutation, Missense; D020641:Polymorphism, Single Nucleotide; D012598:Sclerosis / Q000175:diagnosis / Q000235:genetics*; D017384:Sequence Deletion
chemical_list: C504344:COL6A2 protein, human; D003062:Codon; C553839:Col6a1 protein, human; D024142:Collagen Type VI