Analysis of the role of ZEB1 in the pathogenesis of posterior polymorphous corneal dystrophy.

Purpose: To determine how nonsense mutations in the transcription factor ZEB1 lead to the development of posterior polymorphous corneal dystrophy type 3 (PPCD3).

Methods: Whole-cell extracts were obtained from cultured human corneal epithelial cells (HCEpCs) as a source of ZEB1 protein. DNA-binding assays were performed using the whole-cell extract and oligonucleotide probes consisting of the two conserved E2-box motifs and surrounding nucleotides upstream of COL4A3.

The utility of next-generation sequencing in the evaluation of the posterior polymorphous corneal dystrophy 1 locus.

Purpose: To identify the genetic basis of posterior polymorphous corneal dystrophy 1 (PPCD1) using next-generation sequencing (NGS) of the common PPCD1 support interval, in which Sanger sequencing failed to identify a pathogenic mutation.

Methods: Enrichment of the portion of chromosome 20 containing the common PPCD1 interval was performed on DNA extracted from an affected and an unaffected member of a family previously linked to the PPCD1 locus. NGS using the Roche 454 Titanium platform was performed, followed by computational analysis using NextGENe Software.

TGFB1-induced extracellular expression of TGFBIp and inhibition of TGFBIp expression by RNA interference in a human corneal epithelial cell line.

Purpose: To report the increased production of extracellular transforming growth factor β-induced protein (TGFBIp) by human corneal epithelial cells (HCECs) after induction by TGFB1 and the inhibition of TGFBIp production in induced and noninduced HCECs by RNA interference (RNAi).

Methods: HCECs were cultured in serum-free medium and treated with 0 or 10 ng/mL TGFB1 over a period of 72 hours. Commercially available siRNAs targeting TGFBI mRNA were mixed with a transfection reagent and used to reverse transfect TGFB1-induced and noninduced HCECs.

Linkage of posterior amorphous corneal dystrophy to chromosome 12q21.33 and exclusion of coding region mutations in KERA, LUM, DCN, and EPYC.

Purpose: To identify the genetic basis of posterior amorphous corneal dystrophy (PACD) segregating in a large pedigree.

Methods: The authors performed clinical evaluation of a previously unreported pedigree with PACD, light and electron microscopic examination of an excised corneal button, genomewide linkage analysis, fine mapping linkage and haplotype analysis, and screening of four candidate genes (KERA, LUM, DCN, and EPYC).

Results: Twenty-one participants were determined to be affected based on the presence of characteristic clinical features of PACD; 15 affected and 39 unaffected individuals from a single pedigree enrolled in the study and provided DNA for analysis.

Exclusion of positional candidate gene coding region mutations in the common posterior polymorphous corneal dystrophy 1 candidate gene interval.

Purpose: Posterior polymorphous corneal dystrophy (PPCD) is an autosomal-dominant disorder of the corneal endothelium associated with visually significant corneal edema and glaucoma. Statistical genetic analysis of 4 families with PPCD has demonstrated linkage to a 2.4 cM common support interval on chromosome 20 bordered by the markers D20S182 and D20S139.

Keratoconus associated with corneal stromal amyloid deposition containing TGFBIp.

Purpose: To report the identification and characterization of stromal amyloid deposits in patients with keratoconus.

Methods: The excised corneal buttons from 2 patients diagnosed clinically with keratoconus underwent histochemical analysis with Masson trichrome, Congo red, Alcian blue, and periodic acid-Schiff stains, and immunohistochemical analysis for the transforming growth factor beta-induced gene (TGFBI) protein product (TGFBIp), prealbumin, lysozyme, and kappa and lambda light chain expression. After the collection of DNA from both patients, exons 4, 11, 12, 13 and 14 of TGFBI were amplified and sequenced to search for mutations previously associated with dystrophic corneal stromal amyloid deposition.

Classic lattice corneal dystrophy associated with monoclonal gammopathy after exclusion of a TGFBI mutation.

Purpose: The purpose of this study was to report the association of phenotypic features characteristic of lattice corneal dystrophy (LCD) with a monoclonal gammopathy of undetermined significance (MGUS) after exclusion of a coding region mutation in transforming growth factor beta-induced (TGFBI) gene.

Design: Case report.

Methods: Slit-lamp examination and collection of DNA for TGFBI screening were performed.

A novel variant of combined granular-lattice corneal dystrophy associated with the Met619Lys mutation in the TGFBI gene.

Objective: To report a novel mutation in TGFBI (GenBank NM_000358), p.Met619Lys, associated with a variant of combined granular-lattice corneal dystrophy.

Methods: Slitlamp examination and DNA collection from the proband and affected and unaffected relatives.

Identification of mutations in UBIAD1 following exclusion of coding mutations in the chromosome 1p36 locus for Schnyder crystalline corneal dystrophy.

Purpose: To identify the genetic basis of Schnyder crystalline corneal dystrophy (SCCD) through screening positional candidate genes and UBIAD1, in which mutations have been associated with SCCD, in affected families.

Methods: The coding region of each of the 16 positional candidate genes for which mutation screening has not been previously reported was screened with polymerase chain reaction (PCR) amplification and automated sequencing in four affected individuals from two families with SCCD. In addition, the coding region of UBIAD1, located just outside of the originally described SCCD candidate interval on chromosome 1p36, was directly sequenced in affected and unaffected individuals from three families with SCCD.

Posterior polymorphous corneal dystrophy is associated with TCF8 gene mutations and abdominal hernia.

Mutations in the two-handed zinc-finger homeodomain transcription factor gene (TCF8) have been associated with posterior polymorphous corneal dystrophy (PPCD) and extraocular developmental abnormalities. We performed screening of TCF8 in 32 affected, unrelated probands, affected and unaffected family members of probands identified with a TCF8 mutation, and in 100 control individuals. Eight different pathogenic mutations were identified in eight probands: four frameshift (c.

An unusual presentation of macular corneal dystrophy associated with uniparental isodisomy and a novel Leu173Pro mutation.

Purpose: To report an unusual phenotype of macular corneal dystrophy (MCDC1) associated with a novel CHST6 mutation transmitted via maternal isodisomy.

Methods: Slit lamp examination of the patient and his parents was performed. DNA was collected from each individual for amplification and sequencing of the CHST6 coding region, as well as exons 4 and 12 of TGFBI.

Keratoconus is not associated with mutations in COL8A1 and COL8A2.

Purpose: To evaluate the suggested role of the COL8A1 and COL8A2 genes in the pathogenesis of the corneal ectatic disorders keratoconus and keratoglobus through mutation screening in affected patients.

Methods: DNA extraction, polymerase chain reaction amplification, and sequencing of COL8A1 and COL8A2 were performed in 50 unrelated keratoconus and 2 unrelated keratoglobus patients.

Results: No sequence variations were identified in COL8A1 and COL8A2 in the 2 patients with keratoglobus.

Autosomal recessive CHED associated with novel compound heterozygous mutations in SLC4A11.

Purpose: To determine the genetic basis of autosomal recessive congenital hereditary endothelial dystrophy (CHED2) in an American patient of Chinese ancestry.

Methods: Slit-lamp examination of the proband and his parents, as well as histopathologic examination of excised corneal specimens from the proband, were performed to confirm the diagnosis of autosomal recessive CHED. DNA was collected from the proband and his parents, and all 19 exons of the SLC4A11 gene were amplified and screened.

Autosomal dominant cornea plana is not associated with pathogenic mutations in DCN, DSPG3, FOXC1, KERA, LUM, or PITX2.

Purpose: To determine the genetic basis of autosomal dominant cornea plana (CNA1) through the performance of a genome-wide linkage analysis and screening of the decorin (DCN), dermatan sulfate proteoglycan 3 (DSPG3), forkhead box C1 (FOXC1), keratocan (KERA), lumican (LUM,) and paired-like homeodomain transcription factor 2 (PITX2) genes in members of an affected multigenerational family.

Methods: Cycloplegic refraction, slit lamp biomicroscopy, corneal pachymetry, and corneal topography were performed to determine each patient's affected status. DNA was obtained from affected and unaffected subjects for the performance of a genome-wide linkage analysis as well as PCR amplification and sequencing of DCN, DSPG3, FOXC1, KERA, LUM, and PITX2.

Replication and refinement of linkage of posterior polymorphous corneal dystrophy to the posterior polymorphous corneal dystrophy 1 locus on chromosome 20.

Purpose: The study purpose was to identify the genetic basis of posterior polymorphous corneal dystrophy, an autosomal dominant disorder of the corneal endothelium that is associated with the development of corneal edema, necessitating corneal transplantation for visual rehabilitation. Glaucoma also develops in up to 40% of patients with posterior polymorphous corneal dystrophy.

Methods: Linkage analysis, using microsatellite markers previously used to demonstrate linkage of posterior polymorphous corneal dystrophy to the chromosome 20 candidate region known as posterior polymorphous corneal dystrophy 1, was performed in 29 members of a family with posterior polymorphous corneal dystrophy.

A clinical and histopathologic examination of accelerated TGFBIp deposition after LASIK in combined granular-lattice corneal dystrophy.

Purpose: To report the clinical and histopathologic features of accelerated TGFBI protein (TGFBIp) deposition after lamellar keratorefractive surgery in a patient with combined granular-lattice corneal dystrophy (CGLCD) who underwent bilateral corneal transplantation.

Design: Interventional case report.

Methods: A 28-year-old woman with a presumed TGFBI corneal dystrophy, but who retained best corrected visual acuity of 20/20 in each eye, underwent myopic laser-assisted in-situ keratomileusis (LASIK) both eyes (OU).

No pathogenic mutations identified in the COL8A1 and COL8A2 genes in familial Fuchs corneal dystrophy.

Purpose: To investigate the genetic basis of late-onset, familial Fuchs endothelial corneal dystrophy (FECD) through screening of the COL8A1 and COL8A2 genes, in which mutations have been associated with both early and late-onset, familial and sporadic FECD.

Methods: DNA extraction, PCR amplification, and direct sequencing of the COL8A1 and COL8A2 genes was performed in affected and unaffected members of 15 unrelated families with two or more members with late-onset FECD.

Results: Screening of the COL8A1 gene did not reveal sequence variants in any affected individuals from the 15 FECD families.

No VSX1 gene mutations associated with keratoconus.

Purpose: To determine whether mutations of the VSX1 gene play a pathogenetic role in the development of keratoconus (KTCN).

Methods: DNA extraction, PCR amplification, and direct sequencing of the VSX1 gene were performed in 100 unrelated patients with diagnoses of clinical and topographic features of KTCN.

Results: Of the four previously identified presumed pathogenic mutations in the VSX1 gene (Leu17Pro, Asp144Glu, Leu159Met, and Arg166Trp), only Asp144Glu was identified in a single affected patient.

Unilateral lattice corneal dystrophy associated with the novel His572del mutation in the TGFBI gene.

Purpose: To report a novel mutation in the TGFBI gene, c.1761_1763del (p.His572del), associated with a unilateral variant of lattice corneal dystrophy (LCD).

Analysis of fifteen positional candidate genes for Schnyder crystalline corneal dystrophy.

Purpose: To identify the genetic basis of Schnyder crystalline corneal dystrophy (SCCD) through screening of positional candidate genes in affected patients.

Methods: Mutation screening of fifteen genes (CORT, CLSTN1, CTNNBIP1, DFFA, ENO1, GPR157, H6PD, KIF1B, LOC440559, LZIC, MGC4399, PEX14, PGD, PIK3CD, and SSB1) that lie within the candidate gene region for SCCD was performed in members of two families affected with SCCD.

Results: No presumed disease-causing mutations were identified in affected patients.

A unique corneal dystrophy of Bowman's layer and stroma associated with the Gly623Asp mutation in the transforming growth factor beta-induced (TGFBI) gene.

Purpose: To report a unique corneal dystrophy characterized by deposits at Bowman's layer and stromal lattice lines associated with the Gly623Asp missense mutation in the transforming growth factor beta-induced (TGFBI) gene.

Design: Experimental study.

Participants And Controls: The proband, 3 affected siblings, 4 unaffected relatives, and 100 control individuals.

Pax-6 expression in posthatch chick retina during and recovery from form-deprivation myopia.

The expression of Pax-6 in fully-differentiated chick retina remains largely confined to the amacrine and ganglion cell layers. In the developing posthatch chick retina, Pax-6 expression shows a biphasic pattern; a decrease by posthatch day 17 followed by a steady increase in the adult eye. Interestingly, we find that this biphasic expression of Pax-6 is reflected in the biphasic growth pattern of the posthatch chick eye, which is disrupted by form-deprivation myopia (FDM).

No pathogenic mutations identified in the COL8A2 gene or four positional candidate genes in patients with posterior polymorphous corneal dystrophy.

Purpose: To identify the genetic basis of posterior polymorphous corneal dystrophy (PPCD) through screening of four positional candidate genes and the COL8A2 gene, in which a presumed pathogenic mutation has previously been identified in affected patients.

Methods: DNA extraction, PCR amplification, and direct sequencing of the COL8A2, BFSP1, CST3, MMP9, and SLPI genes were performed in 14 unrelated, affected patients and in unaffected family members.

Results: In the COL8A2 gene, the previously identified, presumed pathogenic mutation (Gln455Lys) was not discovered in any of the affected patients.

Corneal pharmacokinetics of topically applied azithromycin and clarithromycin.

Purpose: To determine corneal levels of topically administered azithromycin and clarithromycin in a rabbit model.

Design: Experimental animal study.

Methods: Corneas of New Zealand albino rabbits were treated with topical azithromycin (2 mg/ml or 4 mg/ml) or clarithromycin (10 mg/ml).