title: TBK1 and flanking genes in human retina.
abstract: OBJECTIVE
  The gene that causes normal tension glaucoma (NTG) in a large pedigree was recently mapped to a region of chromosome 12q14 (GLC1P) that contains the genes TBK1, XPOT, RASSF3, and GNS. We sought to investigate the structure of the chromosome 12q14 duplication and explore the ocular expression of GLC1P locus genes.
  
  
  METHODS
  The location of the chromosome 12q14 duplication in this pedigree was examined with fluorescent in situ hybridization (FISH) using probes for TBK1 and GNS. The expression pattern of XPOT, TBK1, RASSF3, and GNS was investigated with immunohistochemistry of human eyes.
  
  
  RESULTS
  The karyotype of an NTG patient from pedigree GGO-414 was normal and FISH studies demonstrated that the duplicated DNA is organized as a tandem repeat on chromosome 12q14. Of the genes in or near the chromosome 12q14 duplication, TBK1 showed expression in the retina that is specific to the retinal ganglion cells and the retinal nerve fiber layer. Expression of RASSF3 and XPOT was relatively uniform throughout the retina, while GNS expression was expressed in a pattern consistent with Müller cells.
  
  
  CONCLUSIONS
  Previous studies demonstrated that chromosome 12q14 duplications are associated with NTG inherited as an autosomal dominant trait. FISH studies now demonstrate that the duplicated segments are tandemly organized on chromosome 12q14 in close proximity. The specific expression of TBK1 in human retinal ganglion cells compared to the widespread pattern of expression of neighboring genes provides additional evidence that TBK1 is the glaucoma gene in the chromosome 12q14 duplication within the GLC1P locus.
authors: Department of Ophthalmology and Visual Sciences .
authors: John H
authors: JH
authors: Fingert
authors: Benjamin W
authors: BW
authors: Darbro
authors: Qining
authors: Q
authors: Qian
authors: Richard
authors: R
authors: Van Rheeden
authors: Kathy
authors: K
authors: Miller
authors: Megan
authors: M
authors: Riker
authors: Frances
authors: F
authors: Solivan-Timpe
authors: Ben R
authors: BR
authors: Roos
authors: Alan L
authors: AL
authors: Robin
authors: Robert F
authors: RF
authors: Mullins
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002478:Cells, Cultured; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics; D015342:DNA Probes; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D057066:Low Tension Glaucoma / Q000235:genetics*; D008297:Male; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics; D029543:Nucleocytoplasmic Transport Proteins / Q000235:genetics; D010375:Pedigree; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D012165:Retinal Ganglion Cells / Q000378:metabolism*; D012867:Skin / Q000166:cytology; D013429:Sulfatases / Q000235:genetics; D014314:Trisomy / Q000235:genetics*
chemical_list: D015342:DNA Probes; D029543:Nucleocytoplasmic Transport Proteins; C454041:RASSF3 protein, human; C503618:XPOT protein, human; D017346:Protein Serine-Threonine Kinases; C403191:TBK1 protein, human; D013429:Sulfatases; C028553:disulfoglucosamine-6-sulfatase; D020559:Monomeric GTP-Binding Proteins