Congenital hereditary endothelial dystrophy 1 (CHED1) and posterior polymorphous corneal dystrophy 1 (PPCD1) are autosomal-dominant corneal endothelial dystrophies that have been genetically mapped to overlapping loci on the short arm of chromosome 20. We combined genetic and genomic approaches to identify the cause of disease in extensive pedigrees comprising over 100 affected individuals. After exclusion of pathogenic coding, splice-site, and copy-number variations, a parallel approach using targeted and whole-genome sequencing facilitated the identification of pathogenic variants in a conserved region of the OVOL2 proximal promoter sequence in the index families (c.-339_361dup for CHED1 and c.-370T>C for PPCD1). Direct sequencing of the OVOL2 promoter in other unrelated affected individuals identified two additional mutations within the conserved proximal promoter sequence (c.-274T>G and c.-307T>C). OVOL2 encodes ovo-like zinc finger 2, a C2H2 zinc-finger transcription factor that regulates mesenchymal-to-epithelial transition and acts as a direct transcriptional repressor of the established PPCD-associated gene ZEB1. Interestingly, we did not detect OVOL2 expression in the normal corneal endothelium. Our in vitro data demonstrate that all four mutated OVOL2 promoters exhibited more transcriptional activity than the corresponding wild-type promoter, and we postulate that the mutations identified create cryptic cis-acting regulatory sequence binding sites that drive aberrant OVOL2 expression during endothelial cell development. Our data establish CHED1 and PPCD1 as allelic conditions and show that CHED1 represents the extreme of what can be considered a disease spectrum. They also implicate transcriptional dysregulation of OVOL2 as a common cause of dominantly inherited corneal endothelial dystrophies.

• MeSH
• alely * MeSH
• dědičné dystrofie rohovky genetika   MeSH
• DNA MeSH
• lidé MeSH
• mutace * MeSH
• promotorové oblasti (genetika) * MeSH
• rodokmen MeSH
• sekvence nukleotidů MeSH
• sekvenční homologie nukleových kyselin MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Posterior polymorphous corneal dystrophy (PPCD) is a rare autosomal dominant genetically heterogeneous disorder. Nineteen Czech PPCD pedigrees with 113 affected family members were identified, and 17 of these kindreds were genotyped for markers on chromosome 20p12.1- 20q12. Comparison of haplotypes in 81 affected members, 20 unaffected first degree relatives and 13 spouses, as well as 55 unrelated controls, supported the hypothesis of a shared ancestor in 12 families originating from one geographic location. In 38 affected individuals from nine of these pedigrees, a common haplotype was observed between D20S48 and D20S107 spanning approximately 23 Mb, demonstrating segregation of disease with the PPCD1 locus. This haplotype was not detected in 110 ethnically matched control chromosomes. Within the common founder haplotype, a core mini-haplotype was detected for D20S605, D20S182 and M189K2 in all 67 affected members from families 1-12, however alleles representing the core mini-haplotype were also detected in population matched controls. The most likely location of the responsible gene within the disease interval, and estimated mutational age, were inferred by linkage disequilibrium mapping (DMLE+2.3). The appearance of a disease-causing mutation was dated between 64-133 generations. The inferred ancestral locus carrying a PPCD1 disease-causing variant within the disease interval spans 60 Kb on 20p11.23, which contains a single known protein coding gene, ZNF133. However, direct sequence analysis of coding and untranslated exons did not reveal a potential pathogenic mutation. Microdeletion or duplication was also excluded by comparative genomic hybridization using a dense chromosome 20 specific array. Geographical origin, haplotype and statistical analysis suggest that in 14 unrelated families an as yet undiscovered mutation on 20p11.23 was inherited from a common ancestor. Prevalence of PPCD in the Czech Republic appears to be the highest worldwide and our data suggests that at least one other novel locus for PPCD also exists.

• MeSH
• dědičné dystrofie rohovky epidemiologie   genetika   patologie   MeSH
• dominantní geny MeSH
• efekt zakladatele * MeSH
• exony MeSH
• genetická heterogenita MeSH
• genetické lokusy MeSH
• haplotypy MeSH
• lidé MeSH
• lidské chromozomy, pár 20 * MeSH
• mapování chromozomů MeSH
• mutace * MeSH
• prevalence MeSH
• represorové proteiny genetika   MeSH
• rodokmen MeSH
• rohovka metabolismus   patologie   MeSH
• srovnávací genomová hybridizace MeSH
• studie případů a kontrol MeSH
• vazebná nerovnováha * MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH

AIMS: To evaluate mutations in the transforming-growth-factor-beta-induced (TGFBI) gene in patients of Czech origin with autosomal dominant corneal dystrophies. METHODS: The coding sequence of the TGFBI gene was analysed in 22 affected Czech individuals from 7 apparently unrelated families. Comparison of phenotype to genotype was performed. RESULTS: A H626P mutation, previously only described in a family with a variant of lattice corneal dystrophy (LCD), was detected in one family with superficial geographic corneal opacities. Light microscopy of 2 samples obtained following either a prior superficial keratectomy or keratoplasty showed amyloid but no fuchsinophilic deposits. In a family with LCD type I, an R124C mutation was identified. The R124L mutation was shown to be causative of Reis-Bucklers corneal dystrophy in 2 families. A family with Thiel-Behnke corneal dystrophy exhibited an R555Q mutation. In 2 families with granular corneal dystrophy type I, the typical R555W change was identified. CONCLUSION: The phenotype of the family with the H626P mutation differed from the phenotype previously reported for this change.

• MeSH
• amyloid metabolismus   MeSH
• dědičné dystrofie rohovky klasifikace   genetika   metabolismus   MeSH
• dospělí MeSH
• extracelulární matrix - proteiny genetika   MeSH
• fenotyp MeSH
• histidin MeSH
• katarakta genetika   metabolismus   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace * MeSH
• prolin MeSH
• rohovka metabolismus   patologie   MeSH
• transformující růstový faktor beta genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Geografické názvy
• Česká republika MeSH

We describe the search for mutations in six unrelated Czech and four unrelated British families with posterior polymorphous corneal dystrophy (PPCD); a relatively rare eye disorder. Coding exons and intron/exon boundaries of all three genes (VSX1, COL8A2, and ZEB1/TCF8) previously reported to be implicated in the pathogenesis of this disorder were screened by DNA sequencing. Four novel pathogenic mutations were identified in four families; two deletions, one nonsense, and one duplication within exon 7 in the ZEB1 gene located at 10p11.2. We also genotyped the Czech patients to test for a founder haplotype and lack of disease segregation with the 20p11.2 locus we previously described. Although a systematic clinical examination was not performed, our investigation does not support an association between ZEB1 changes and self reported non-ocular anomalies. In the remaining six families no disease causing mutations were identified thereby indicating that as yet unidentified gene(s) are likely to be responsible for PPCD.

• MeSH
• dědičné dystrofie rohovky genetika   MeSH
• dospělí MeSH
• homeodoménové proteiny genetika   MeSH
• kolagen typ VIII genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• oční proteiny genetika   MeSH
• rodokmen MeSH
• senioři MeSH
• transkripční faktor Zeb1 MeSH
• transkripční faktory genetika   MeSH
• vzácné nemoci genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Spojené království MeSH

Posterior polymorphous corneal dystrophy (PPCD) is a hereditary bilateral disorder affecting Descemet's membrane and the endothelium. The aim of the present study was to determine the spectrum of cytokeratin (CK) expression in cells on the posterior surface of the cornea in PPCD patients. Ten corneal buttons and one specimen of the trabecular meshwork (TM) from PPCD patients who underwent graft or glaucoma surgery were used, as well as six corneal buttons and two TM specimens obtained from healthy donors as controls. Cryosections were fixed and indirect immunofluorescent staining was performed using antibodies directed against a wide spectrum of cytokeratins (CKs). The number of positive cells and the intensity of the staining were assessed using fluorescent microscopy. All 10 PPCD corneal specimens had areas of endothelium displaying typical endothelial morphology as well as areas consisting of layers two to six cells thick with both flat endothelial-like cells and polygonal cells with round nuclei and a large cytoplasm. Both of these morphologically distinct cell types showed strong immunostaining for CK7, CK19, CK8 and CK18, while weaker positive signals were observed for CK1, CK3/12, CK4, CK5/6, CK10, CK10/13, CK14, CK16 and CK17. PPCD endothelium was completely negative for CK2e, CK9, CK15, and CK20. Focal positivity was detected in PPCD TM for CK4, CK7 and CK19. CK8 and CK18 were the only CKs expressed in control endothelium. PPCD and control epithelium displayed similar staining patterns. The distinct positivity for CK3/12, CK4, CK5/6, CK10/13, CK14, CK16 and CK17 was observed in aberrant PPCD endothelium for the first time. We demonstrate that the abnormal endothelium of PPCD patients expresses a mixture of CKs, with CK7 and CK19 predominating. In terms of CK composition, the aberrant PPCD endothelium shares features of both simple and squamous stratified epithelium with a proliferative capacity. The wide spectrum of CK expression is most probably not indicative of the transformation of endothelial cells to a distinct epithelial phenotype, but more likely reflects the modified differentiation of metaplastic epithelium.

• MeSH
• dědičné dystrofie rohovky metabolismus   patologie   MeSH
• financování organizované MeSH
• fluorescenční mikroskopie metody   MeSH
• imunohistochemie metody   MeSH
• keratiny typu I analýza   MeSH
• keratiny typu II analýza   MeSH
• keratiny analýza   MeSH
• lidé středního věku MeSH
• lidé MeSH
• oční proteiny analýza   MeSH
• rohovkový endotel abnormality   metabolismus   patologie   MeSH
• trabekulární síť metabolismus   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH

• MeSH
• dědičné dystrofie rohovky * diagnóza   etiologie   genetika   patologie   MeSH
• exony genetika   MeSH
• genetické testování * metody   využití   MeSH
• introny genetika   MeSH
• lidé MeSH
• mutace MeSH
• prospektivní studie MeSH
• rohovkový endotel patologie   MeSH
• sekvenční analýza MeSH
• transformující růstový faktor beta1 diagnostické užití   MeSH
• úbytek endoteliálních buněk rohovky genetika   MeSH
• Check Tag
• lidé MeSH
• Geografické názvy
• Česká republika MeSH
• Spojené království MeSH

PURPOSE: Posterior polymorphous corneal dystrophy (PPCD) is an autosomal dominant disorder, affecting both the corneal endothelium and Descemet's membrane. In the Czech Republic, PPCD is one of the most prevalent corneal dystrophies. The purpose of this study was to determine the chromosomal locus of PPCD in two large Czech families, by using linkage analysis. METHODS: Linkage analysis was performed on 52 members of two Czech families with PPCD and polymorphic microsatellite markers and lod scores were calculated. The candidate gene VSX1 was also screened for mutations. RESULTS: Significant lod scores were obtained with microsatellite markers on chromosome 20. Linkage analysis delineated the Czech PPCD locus to a 2.7-cM locus on chromosome 20, region p11.2, between flanking markers D20S48 and D20S139, which excluded VSX1 as the disease-causing gene in both families. In addition, the exclusion of VSX1 was confirmed by sequence analysis. CONCLUSIONS: This study reports the localization of PPCD in patients of Czech origin to chromosome 20 at p11.2. Linkage data and sequence analysis exclude VSX1 as causative of PPCD in two Czech families. This refined locus for PPCD overlaps the congenital hereditary endothelial dystrophy (CHED1) disease interval, and it is possible that these corneal dystrophies are allelic.

• MeSH
• dědičné dystrofie rohovky epidemiologie   genetika   patologie   MeSH
• Descemetova membrána patologie   MeSH
• genetické markery MeSH
• homeodoménové proteiny genetika   MeSH
• lidé MeSH
• lidské chromozomy, pár 20 genetika   MeSH
• lod skóre MeSH
• lokus kvantitativního znaku MeSH
• mapování chromozomů * MeSH
• oční proteiny genetika   MeSH
• rodokmen MeSH
• rohovkový endotel patologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH