Purpose. Recoverin is an abundantly expressed, retina-specific, calcium-binding protein that contains four EF-hand calcium-binding domains. Recoverin serves as a calcium sensor in photoreceptors and is believed to affect the termination of the phototransduction cascade thereby participating in visual adaptation (Gray-Keller et al. Neuron 10:523-531, 1993). In view of this purported function, it is reasonable to propose that a defect in the gene encoding recoverin could lead to abnormal vision. The human recoverin gene encompasses 9-10 kb on chromosome 17p13.1. Here, we report an ongoing evaluation of retinitis pigmentosa (RP) and allied diseases for mutations in the recoverin gene. Methods. We are using SSCP analysis and direct genomic sequencing techniques to screen 858 unrelated patients, including 198 patients with dominant RP, 206 patients with recessive RP, and 453 patients with an allied disease. Using oligonucleotide primers based on the genomic sequence flanking the coding regions, we are screening for mutations in the entire coding region of the human recoverin gene as well as some of the flanking intron and 5′ and 3′ untranslated sequences. Results. To date, we have screened all three exons in 858 patients and have found one Ala200Thr missense change in a single patient with dominant RP that does not cosegregate with disease. We have also found 2 silent polymorphisms affecting codons Pro190 and Ser24. Conclusions. We are proceeding with sequence analysis of 15 variant bands and cosegregation studies of any remaining sequence abnormalities that affect protein structure or expression. Our negative screen to date is consistent with the absence of retinal degeneration in recoverin knockout mice (D.A. Baylor et al. IOVS 36(4):2932, 1995).
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience