Genomic structure and assessment of the retinally expressed RFamide-related peptide gene in dominant cystoid macular dystrophy

Mol Vis. 2002 Mar 19;8:67-71.

Abstract

Purpose: Computer-assisted sampling of EST data contained within the UniGene human sequences collection is being used to establish a catalog of novel genes that are expressed exclusively or predominantly in the human retina. This provides a valuable source for candidate genes possibly involved in retinal degeneration. In this report we present the characterization of the C7orf9 gene locus encoding RFamide-related peptides (RFRPs) and its evaluation in dominant cystoid macular dystrophy (CYMD).

Methods: Bioinformatics and cDNA library screening were used to isolate the full-length cDNA sequence and to determine the genomic organization of C7orf9. Expression profiling was done by RT-PCR and Northern blot analysis. C7orf9 was evaluated as a candidate gene for CYMD by DNA sequencing and Southern blot analysis in two affected individuals from an extended Dutch CYMD family.

Results: The C7orf9 cDNA transcript consists of 1190 bp and is organized into 3 exons on the short arm of chromosome 7 within the critical region for CYMD. The transcript is specifically expressed in the retina but not in a large range of other human tissues. No disease-causing mutations or larger gene rearrangements were found.

Conclusions: We provide the genomic organization of the RFamide-related peptide gene, C7orf9, which encodes a precursor protein for at least two small neuropeptides, referred to as NPSF (alias RFRP-1) and NPVF (alias RFRP-3) and show that it is abundantly expressed in the human retina. Results of our comprehensive mutation analysis suggests that C7orf9 is not the CYMD gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Northern
  • Blotting, Southern
  • Chromosomes, Human, Pair 7 / genetics
  • DNA Mutational Analysis
  • DNA Primers / chemistry
  • Eye Proteins / genetics*
  • Eye Proteins / metabolism
  • Gene Expression
  • Gene Expression Profiling
  • Gene Library
  • Genes, Dominant
  • Genetic Linkage
  • Humans
  • Macular Edema / genetics*
  • Macular Edema / metabolism
  • Molecular Sequence Data
  • Neuropeptides / genetics*
  • Neuropeptides / metabolism
  • Retina / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA

Substances

  • DNA Primers
  • Eye Proteins
  • NPVF protein, human
  • Neuropeptides
  • RFamide peptide