title: Evaluation of the gene encoding the gamma subunit of rod phosphodiesterase in retinitis pigmentosa.
abstract: OBJECTIVE
  To determine whether defects in the gene encoding the gamma subunit of rod cyclic guanosine monophosphate-phosphodiesterase (PDE-g) cause some form of hereditary retinal degeneration or dysfunction.
  
  
  METHODS
  A restriction map, an intron/exon map, and a partial sequence of the human genomic locus corresponding to this gene were ascertained. Based on this information, the single-strand conformation polymorphism technique (SSCP) was used to screen the coding region as well as most splice donor and acceptor sites for mutations in a total of 704 unrelated patients with retinitis pigmentosa, Usher's syndrome type I or type II, Leber's congenital amaurosis, the Laurence-Moon-Bardet-Biedl syndrome, or other hereditary retinal disease.
  
  
  RESULTS
  Two frequent polymorphisms were found, as well as three rare sequence variations, none of which correlated with any phenotype examined.
  
  
  CONCLUSIONS
  In view of these negative results and those of a previously published negative Southern blot analysis of an overlapping set of patients, it is unlikely that mutations in the PDE-g gene are a common cause of any of the forms of retinal degeneration or dysfunction so far examined.
authors.affiliation: Howe Laboratory, Massachusetts Eye and Ear Infirmary, Boston 02114.
authors.forename: L B
authors.initials: LB
authors.lastname: Hahn
authors.forename: E L
authors.initials: EL
authors.lastname: Berson
authors.forename: T P
authors.initials: TP
authors.lastname: Dryja
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000235:genetics*; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D015342:DNA Probes; D005069:Evaluation Studies as Topic; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D010375:Pedigree; D017354:Point Mutation; D011110:Polymorphism, Genetic; D015183:Restriction Mapping; D012164:Retinal Diseases / Q000201:enzymology / Q000235:genetics; D012174:Retinitis Pigmentosa / Q000201:enzymology* / Q000235:genetics; D012374:Rod Cell Outer Segment / Q000201:enzymology*
chemical_list: D015342:DNA Probes; D015106:3',5'-Cyclic-GMP Phosphodiesterases