title: Localization of SH3PXD2B in human eyes and detection of rare variants in patients with anterior segment diseases and glaucoma.
abstract: OBJECTIVE
  Analysis of mutant mouse strains and linkage analysis with human families have both demonstrated that mutations influencing the podosomal adaptor protein SH3 and PX domains 2B (SH3PXD2B) can result in a congenital form of glaucoma. Here, we use immunohistochemistry to describe localization of the SH3PXD2B protein throughout the adult human eye and test whether sequence variants in SH3PXD2B occur in multiple other forms of glaucoma.
  
  
  METHODS
  In immunohistochemical experiments, cryosections of human donor eyes were evaluated for SH3PXD2B immunoreactivity with a polyclonal antibody. In genetic experiments, exon sequences of SH3PXD2B from patients with primary congenital glaucoma (n=21), Axenfeld-Rieger syndrome (n=30), and primary open angle glaucoma (n=127) were compared to control subjects (n=89). The frequency of non-synonymous SH3PXD2B coding sequence variants were compared between patient cohorts and controls using Fisher's exact test.
  
  
  RESULTS
  Varying intensities of SH3PXD2B immunoreactivity were detected in almost all ocular tissues. Among tissues important to glaucoma, immunoreactivity was detected in the drainage structures of the iridocorneal angle, ciliary body, and retinal ganglion cells. Intense immunoreactivity was present in photoreceptor inner segments. From DNA analysis, a total of 11 non-synonymous variants were detected. By Fisher's Exact test, there was not a significant skew in the overall frequency of these changes in any patient cohort versus controls (p-value >0.05). Each cohort contained unique variants not detected in other cohorts or patients.
  
  
  CONCLUSIONS
  SH3PXD2B is widely distributed in the adult human eye, including several tissues important to glaucoma pathogenesis. Analysis of DNA variants in three forms of glaucoma detected multiple variants unique to each patient cohort. While statistical analysis failed to support a pathogenic role for these variants, some of them may be rare disease-causing variants whose biologic significance warrants investigation in follow up replication studies and functional assays.
authors.affiliation: Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, IA, USA.
authors.forename: Mao
authors.initials: M
authors.lastname: Mao
authors.forename: Frances
authors.initials: F
authors.lastname: Solivan-Timpe
authors.forename: Ben R
authors.initials: BR
authors.lastname: Roos
authors.forename: Robert F
authors.initials: RF
authors.lastname: Mullins
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Oetting
authors.forename: Young H
authors.initials: YH
authors.lastname: Kwon
authors.forename: Peter M
authors.initials: PM
authors.lastname: Brzeskiewicz
authors.forename: Edwin M
authors.initials: EM
authors.lastname: Stone
authors.forename: Wallace L M
authors.initials: WL
authors.lastname: Alward
authors.forename: Michael G
authors.initials: MG
authors.lastname: Anderson
authors.forename: John H
authors.initials: JH
authors.lastname: Fingert
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D000869:Anterior Eye Segment / Q000002:abnormalities / Q000378:metabolism / Q000473:pathology*; D001344:Autopsy; D016022:Case-Control Studies; D005091:Exons; D005124:Eye Abnormalities / Q000235:genetics* / Q000473:pathology; D015785:Eye Diseases, Hereditary; D005901:Glaucoma / Q000151:congenital / Q000235:genetics* / Q000473:pathology; D005902:Glaucoma, Open-Angle / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA; D014481:United States
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C547814:SH3PXD2B protein, human