title: Microarray-based mutation detection and phenotypic characterization in Korean patients with retinitis pigmentosa.
abstract: OBJECTIVE
  To evaluate microarray-based genotyping technology for the detection of mutations responsible for retinitis pigmentosa (RP) and to perform phenotypic characterization of patients with pathogenic mutations.
  
  
  METHODS
  DNA from 336 patients with RP and 360 controls was analyzed using the GoldenGate assay with microbeads containing 95 previously reported disease-associated mutations from 28 RP genes. Mutations identified by microarray-based genotyping were confirmed by direct sequencing. Segregation analysis and phenotypic characterization were performed in patients with mutations. The disease severity was assessed by visual acuity, electroretinography, optical coherence tomography, and kinetic perimetry.
  
  
  RESULTS
  Ten RP-related mutations of five RP genes (PRP3 pre-mRNA processing factor 3 homolog [PRPF3], rhodopsin [RHO], phosphodiesterase 6B [PDE6B], peripherin 2 [PRPH2], and retinitis pigmentosa 1 [RP1]) were identified in 26 of the 336 patients (7.7%) and in six of the 360 controls (1.7%). The p.H557Y mutation in PDE6B, which was homozygous in four patients and heterozygous in nine patients, was the most frequent mutation (2.5%). Mutation segregation was assessed in four families. Among the patients with missense mutations, the most severe phenotype occurred in patients with p.D984G in RP1; less severe phenotypes occurred in patients with p.R135W in RHO; a relatively moderate phenotype occurred in patients with p.T494M in PRPF3, p.H557Y in PDE6B, or p.W316G in PRPH2; and a mild phenotype was seen in a patient with p.D190N in RHO.
  
  
  CONCLUSIONS
  The results reveal that the GoldenGate assay may not be an efficient method for molecular diagnosis in RP patients with rare mutations, although it has proven to be reliable and efficient for high-throughput genotyping of single-nucleotide polymorphisms. The clinical features varied according to the mutations. Continuous effort to identify novel RP genes and mutations in a population is needed to improve the efficiency and accuracy of the genetic diagnosis of RP.
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Cinoo
authors.initials: C
authors.lastname: Kim
authors.forename: Kwang Joong
authors.initials: KJ
authors.lastname: Kim
authors.forename: Jeong
authors.initials: J
authors.lastname: Bok
authors.forename: Eun-Ju
authors.initials: EJ
authors.lastname: Lee
authors.forename: Dong-Joon
authors.initials: DJ
authors.lastname: Kim
authors.forename: Ji Hee
authors.initials: JH
authors.lastname: Oh
authors.forename: Sung Pyo
authors.initials: SP
authors.lastname: Park
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Shin
authors.forename: Jong-Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Hyeong Gon
authors.initials: HG
authors.lastname: Yu
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics*; D054707:Cyclic Nucleotide Phosphodiesterases, Type 6 / Q000235:genetics*; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D008869:Microtubule-Associated Proteins; D008875:Middle Aged; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D010375:Pedigree; D064531:Peripherins; D012174:Retinitis Pigmentosa / Q000235:genetics*; D012243:Rhodopsin / Q000235:genetics*; D017414:Ribonucleoprotein, U4-U6 Small Nuclear / Q000235:genetics; D017422:Sequence Analysis, DNA; D012720:Severity of Illness Index; D014792:Visual Acuity
chemical_list: D005136:Eye Proteins; D007381:Intermediate Filament Proteins; D008562:Membrane Glycoproteins; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; C108507:PRPF3 protein, human; C578994:PRPH protein, human; C578997:PRPH2 protein, human; D064531:Peripherins; C120042:RP1 protein, human; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D012243:Rhodopsin; D054707:Cyclic Nucleotide Phosphodiesterases, Type 6; C517431:PDE6B protein, human