title: Unaltered myocilin expression in the blood of primary open angle glaucoma patients.
abstract: OBJECTIVE
  To investigate the expression of the myocilin gene (MYOC) in the blood of primary open angle glaucoma (POAG) patients to determine if altered systemic expression is playing a role.
  
  
  METHODS
  Patients (n=47) were eligible for inclusion if they met standard clinical criteria for POAG. Control subjects (n=27) were recruited who were free from glaucoma by examination. RNA was extracted from leukocytes of patients and controls and converted to cDNA by reverse transcriptase enzyme, and quantitative PCR was used to assess expression levels of MYOC and the house keeping gene β-globulin (HBB). The ratio of MYOC expression to HBB expression for POAG patients was compared to that of controls and to clinical characteristics of POAG patients.
  
  
  RESULTS
  Mean gene expression values were statistically similar in POAG patients and controls for both MYOC (p≤0.55) and HBB (p≤0.48). MYOC/HBB ratios were also statistically indistinguishable between POAG patients and controls (p≤0.90). MYOC/HBB ratios were not significantly associated with age, sex, or ethnicity of patients within the POAG group. Similarly, MYOC/HBB ratios were not significantly associated with clinical parameters related to POAG severity, including maximum intraocular pressure, vertical cup-to-disk ratio, static perimetry mean deviation, or static perimetry pattern standard deviation.
  
  
  CONCLUSIONS
  MYOC expression is not altered in the blood of POAG patients, unlike MYOC expression in trabecular meshwork (TM) cultures. These results suggests that MYOC expression is not altered systemically but rather that MYOC expression may contribute to POAG pathogenesis in specific tissues such as TM.
authors.affiliation: Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia. abuamero@gmail.com
authors.forename: Khaled K
authors.initials: KK
authors.lastname: Abu-Amero
authors.forename: Taif Anwar
authors.initials: TA
authors.lastname: Azad
authors.forename: George L
authors.initials: GL
authors.lastname: Spaeth
authors.forename: Jonathan
authors.initials: J
authors.lastname: Myers
authors.forename: L Jay
authors.initials: LJ
authors.lastname: Katz
authors.forename: Marlene
authors.initials: M
authors.lastname: Moster
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Bosley
mesh_terms: D000368:Aged; D001609:Beta-Globulins / Q000235:genetics; D044383:Black People / Q000235:genetics*; D016022:Case-Control Studies; D003598:Cytoskeletal Proteins / Q000097:blood / Q000235:genetics*; D005136:Eye Proteins / Q000097:blood / Q000235:genetics*; D005260:Female; D015870:Gene Expression; D005902:Glaucoma, Open-Angle / Q000097:blood / Q000235:genetics*; D006023:Glycoproteins / Q000097:blood / Q000235:genetics*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D015143:Philadelphia; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012720:Severity of Illness Index; D014129:Trabecular Meshwork / Q000378:metabolism; D058609:Visual Field Tests; D044465:White People / Q000235:genetics*; D001741:Black or African American; D000099179:Myocilin
chemical_list: D001609:Beta-Globulins; D003598:Cytoskeletal Proteins; D005136:Eye Proteins; D006023:Glycoproteins; D000099179:Myocilin