title: Myocilin mt.1 gene promoter single nucleotide polymorphism (-1000C>G) in Brazilian patients with primary open angle glaucoma.
abstract: BACKGROUND
  The myocilin (MYOC) gene promoter polymorphism -1000C>G (MYOC mt.1) can be associated with faster progression of primary open angle glaucoma (POAG). The purpose of this study was to investigate the MYOC mt.1 in Brazilian patients with POAG and to evaluate its possible role on the phenotype and the severity of the disease.
  
  
  METHODS
  One hundred sixty-seven POAG patients and 130 normal controls were enrolled. DNA samples were prepared and the MYOC mt.1 polymorphism was screened by real-time polymerase chain reaction (RT-PCR) in an Single-nucleotide polymorphism (SNP) assay. Frequencies of the MYOC mt.1 promoter polymorphism were determined for both groups and compared by Fisher's exact test and Chi-square test with Yate's correction. Intraocular pressure (IOP), cup-to-disc ratio (C/D), number of glaucoma medications, and number of glaucoma surgeries were compared between MYOC mt.1 carriers and non-carriers.
  
  
  RESULTS
  MYOC mt.1 genotype frequencies did not differ between POAG and controls (P  =  0.420); 14.6% of controls and 16.4% of POAG patients were MYOC mt.1 carriers (CG or GG). Frequencies of the G allele were similar between glaucomatous patients and controls (7.3% and 9.2%, respectively; P  =  0.477). Among POAG patients, there were no differences in mean C/D ratio, IOP, number of glaucoma medications, and surgical procedures for IOP control between carries and non-carriers of the MYOC mt.1 promoter polymorphism (p>0.05).
  
  
  CONCLUSIONS
  The G allele of the MYOC mt.1 promoter polymorphism was equally distributed among POAG patients and healthy subjects and it is possibly unrelated to the risk and severity of disease in the Brazilian population.
authors.affiliation: Irmandade da Santa Casa de Misericordia de Sao Paulo, Department of Ophthalmology, School of Medical Sciences, Sao Paulo, Brazil. nirokasahara@ig.com.br
authors.forename: Niro
authors.initials: N
authors.lastname: Kasahara
authors.forename: Cristiano
authors.initials: C
authors.lastname: Caixeta-Umbelino
authors.forename: Maurício D
authors.initials: MD
authors.lastname: Paolera
authors.forename: Mylene N
authors.initials: MN
authors.lastname: Rocha
authors.forename: Flávio
authors.initials: F
authors.lastname: Richeti
authors.forename: José P C
authors.initials: JP
authors.lastname: Vasconcellos
authors.forename: Ralph
authors.initials: R
authors.lastname: Cohen
authors.forename: Vital P
authors.initials: VP
authors.lastname: Costa
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Longui
authors.forename: Murilo R
authors.initials: MR
authors.lastname: Melo
authors.forename: Mônica B
authors.initials: MB
authors.lastname: Melo
mesh_terms: D000368:Aged; D001938:Brazil / Q000453:epidemiology; D003598:Cytoskeletal Proteins / Q000235:genetics*; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D005902:Glaucoma, Open-Angle / Q000208:ethnology / Q000235:genetics*; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000099179:Myocilin
chemical_list: D003598:Cytoskeletal Proteins; D005136:Eye Proteins; D006023:Glycoproteins; D000099179:Myocilin