title: A novel GPR143 duplication mutation in a Chinese family with X-linked congenital nystagmus.
abstract: OBJECTIVE
  To elucidate the molecular genetic defect of X-linked congenital nystagmus in a Chinese family.
  
  
  METHODS
  Genomic DNA was prepared from peripheral blood. We used allele-sharing analysis to identify the possible locus harboring the disease-causing gene. We screened for mutations in the G protein-coupled receptor 143 gene (GPR143) by direct sequencing of the polymerase chain reaction (PCR)-amplified exons.
  
  
  RESULTS
  In analyzing the candidate gene, GPR143, in the linked region, a 19 base pair (bp) duplication mutation in exon 1 was detected after direct DNA sequence analysis, which cosegregated in all patients of this family and was present in obligate female carriers.
  
  
  CONCLUSIONS
  The identified 19 bp duplication in GPR143 induces a frame-shift and a premature stop codon, resulting in a truncated protein of 105 residues. These results suggest that this novel mutation is associated with the congenital nystagmus observed in this Chinese family and further support that GPR143 mutations are the underlying pathogenesis of the molecular mechanism for congenital nystagmus.
authors.affiliation: Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Peng
authors.forename: Yan
authors.initials: Y
authors.lastname: Meng
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.forename: Mei
authors.initials: M
authors.lastname: Qin
authors.forename: Xiaoqiao
authors.initials: X
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Dian
authors.forename: Shangzhi
authors.initials: S
authors.lastname: Huang
mesh_terms: D002681:China; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D050172:Genes, X-Linked; D040181:Genetic Diseases, X-Linked / Q000235:genetics*; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D009154:Mutation; D020417:Nystagmus, Congenital / Q000235:genetics*; D010375:Pedigree; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D005136:Eye Proteins; C095276:GPR143 protein, human; D008562:Membrane Glycoproteins