Samuel G. Jacobson

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The relationship between the neurosensory photoreceptors and the adjacent retinal pigment epithelium (RPE) controls not only normal retinal function, but also the pathogenesis of hereditary retinal degenerations. The molecular bases for both primary photoreceptor and RPE diseases that cause blindness have been identified. Gene therapy has been used(More)
Leber congenital amaurosis (LCA) is a group of autosomal recessive blinding retinal diseases that are incurable. One molecular form is caused by mutations in the RPE65 (retinal pigment epithelium-specific 65-kDa) gene. A recombinant adeno-associated virus serotype 2 (rAAV2) vector, altered to carry the human RPE65 gene (rAAV2-CBSB-hRPE65), restored vision(More)
Hereditary human retinal degenerative diseases usually affect the mature photoreceptor topography by reducing the number of cells through apoptosis, resulting in loss of visual function. Only one inherited retinal disease, the enhanced S-cone syndrome (ESCS), manifests a gain in function of photoreceptors. ESCS is an autosomal recessive retinopathy in which(More)
Mutation of a receptor tyrosine kinase gene, Mertk, in the Royal College of Surgeons (RCS) rat results in defective phagocytosis of photoreceptor outer segments by the retinal pigment epithelium (RPE) and retinal degeneration. We screened the human orthologue, MERTK, located at 2q14.1 (ref. 10), in 328 DNA samples from individuals with various retinal(More)
During development, visual photoreceptors, bipolar cells and other neurons establish connections within the retina enabling the eye to process visual images over approximately 7 log units of illumination. Within the retina, cells that respond to light increment and light decrement are separated into ON- and OFF-pathways. Hereditary diseases are known to(More)
We recently showed that mutations in the CNGA3 gene encoding the alpha-subunit of the cone photoreceptor cGMP-gated channel cause autosomal recessive complete achromatopsia linked to chromosome 2q11. We now report the results of a first comprehensive screening for CNGA3 mutations in a cohort of 258 additional independent families with hereditary cone(More)
The RPE65 gene encodes the isomerase of the retinoid cycle, the enzymatic pathway that underlies mammalian vision. Mutations in RPE65 disrupt the retinoid cycle and cause a congenital human blindness known as Leber congenital amaurosis (LCA). We used adeno-associated virus-2-based RPE65 gene replacement therapy to treat three young adults with RPE65-LCA and(More)
OBJECTIVE To assess the frequency of mutations in the CRX, GUCY2D, and RPE65 genes in patients with Leber congenital amaurosis (LCA). PATIENTS One hundred seventy-six probands with a clinical diagnosis of LCA were from 9 countries, with the largest subgroup being 39 probands from India. METHODS Samples were screened with single-strand conformation(More)
The rd3 mouse is one of the oldest identified models of early-onset retinal degeneration. Using the positional candidate approach, we have identified a C-->T substitution in a novel gene, Rd3, that encodes an evolutionarily conserved protein of 195 amino acids. The rd3 mutation results in a predicted stop codon after residue 106. This change is observed in(More)
Rhodopsin kinase (RK), a specialized G-protein-coupled receptor kinase expressed in retina, is involved in quenching of light-induced signal transduction in photoreceptors. The role of RK in recovery after photoactivation has been explored in vitro and in vivo experimentally but has not been specifically defined in humans. We investigated the effects on(More)