title: A dominant mutation in RPE65 identified by whole-exome sequencing causes retinitis pigmentosa with choroidal involvement.
abstract: Linkage testing using Affymetrix 6.0 SNP Arrays mapped the disease locus in TCD-G, an Irish family with autosomal dominant retinitis pigmentosa (adRP), to an 8.8 Mb region on 1p31. Of 50 known genes in the region, 11 candidates, including RPE65 and PDE4B, were sequenced using di-deoxy capillary electrophoresis. Simultaneously, a subset of family members was analyzed using Agilent SureSelect All Exome capture, followed by sequencing on an Illumina GAIIx platform. Candidate gene and exome sequencing resulted in the identification of an Asp477Gly mutation in exon 13 of the RPE65 gene tracking with the disease in TCD-G. All coding exons of genes not sequenced to sufficient depth by next generation sequencing were sequenced by di-deoxy sequencing. No other potential disease-causing variants were found to segregate with disease in TCD-G. The Asp477Gly mutation was not present in Irish controls, but was found in a second Irish family provisionally diagnosed with choroideremia, bringing the combined maximum two-point LOD score to 5.3. Mutations in RPE65 are a known cause of recessive Leber congenital amaurosis (LCA) and recessive RP, but no dominant mutations have been reported. Protein modeling suggests that the Asp477Gly mutation may destabilize protein folding, and mutant RPE65 protein migrates marginally faster on SDS-PAGE, compared with wild type. Gene therapy for LCA patients with RPE65 mutations has shown great promise, raising the possibility of related therapies for dominant-acting mutations in this gene.
authors.affiliation: Human Genetics Center, The University of Texas Health Science Center, Houston, TX, USA.
authors.forename: Sara J
authors.initials: SJ
authors.lastname: Bowne
authors.forename: Marian M
authors.initials: MM
authors.lastname: Humphries
authors.forename: Lori S
authors.initials: LS
authors.lastname: Sullivan
authors.forename: Paul F
authors.initials: PF
authors.lastname: Kenna
authors.forename: Lawrence C S
authors.initials: LC
authors.lastname: Tam
authors.forename: Anna S
authors.initials: AS
authors.lastname: Kiang
authors.forename: Matthew
authors.initials: M
authors.lastname: Campbell
authors.forename: George M
authors.initials: GM
authors.lastname: Weinstock
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Koboldt
authors.forename: Li
authors.initials: L
authors.lastname: Ding
authors.forename: Robert S
authors.initials: RS
authors.lastname: Fulton
authors.forename: Erica J
authors.initials: EJ
authors.lastname: Sodergren
authors.forename: Denis
authors.initials: D
authors.lastname: Allman
authors.forename: Sophia
authors.initials: S
authors.lastname: Millington-Ward
authors.forename: Arpad
authors.initials: A
authors.lastname: Palfi
authors.forename: Alex
authors.initials: A
authors.lastname: McKee
authors.forename: Susan H
authors.initials: SH
authors.lastname: Blanton
authors.forename: Susan
authors.initials: S
authors.lastname: Slifer
authors.forename: Ioanna
authors.initials: I
authors.lastname: Konidari
authors.forename: G Jane
authors.initials: GJ
authors.lastname: Farrar
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Daiger
authors.forename: Peter
authors.initials: P
authors.lastname: Humphries
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D015794:Choroideremia / Q000175:diagnosis / Q000235:genetics*; D004252:DNA Mutational Analysis; D059472:Exome; D005136:Eye Proteins / Q000737:chemistry / Q000235:genetics*; D005260:Female; D005799:Genes, Dominant; D008040:Genetic Linkage; D005838:Genotype; D006367:HeLa Cells; D006801:Humans; D007494:Ireland; D008297:Male; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide; D012174:Retinitis Pigmentosa / Q000175:diagnosis / Q000235:genetics*; D017422:Sequence Analysis, DNA / Q000379:methods*; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase
chemical_list: D002352:Carrier Proteins; D005136:Eye Proteins; D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase