ADAMTS17 mutation associated with primary lens luxation is widespread among breeds.

Primary lens luxation (PLL) is a well-recognized, painful and potentially blinding inherited ocular condition in dogs. We screened PLL-affected dogs of 30 different breeds, to identify those which carried a previously described c.1473+1 G>A mutation in ADAMTS17 that is associated with PLL in Miniature Bull terriers, Lancashire Heelers, and Jack Russell terriers. This ADAMTS17 mutation was identified in PLL-affected dogs from 14 additional breeds. PLL-affected dogs from some breeds (most notably the Shar pei and the Brittany spaniel) did not carry the G1473+1A ADAMTS17 mutation, indicating they must suffer from a genetically distinct form of the condition. We also estimated the frequency of this ADAMTS17 mutation in some of the breeds. Our findings indicate the mutation segregates in a large number of different breeds of dog, many of which are terriers or breeds with terrier co-ancestry, but some of which have more diverse origins. Our results also indicate that the mutation is present at high frequency within most of the breeds in which it segregates. In the miniature bull terrier breed estimates of mutation frequency ranged from 0.27 to 0.39, corresponding to 7.3-15.2% PLL-affected dogs in this breed. We also identified an increased risk of PLL associated with heterozygosity at ADAMTS17, suggesting that carriers carry a low risk of developing PLL.

Long-term myofibroblast persistence in the capsular bag contributes to the late spontaneous in-the-bag intraocular lens dislocation.

Late spontaneous in-the-bag intraocular lens (IOL) dislocation is a complication presenting 6 months or later after cataract surgery. We aimed to characterize the cells in the lens capsules (LCs) of 18 patients with spontaneous late in-the-bag IOL dislocation. Patients' average age was 82.6 ± 1.5 years (range 72-98), and most of them had pseudoexfoliation syndrome (PEX). Cells from the LCs were positive for myofibroblast (αSMA), proliferation (Ki-67, PCNA), early lens development/lens progenitor (SOX2, PAX6), chemokine receptor (CXCR4), and transmembrane (N-cadherin) markers, while negative for epithelial (E-cadherin) marker. Moreover, the cells produced abundant fibronectin, type I and type V collagen in the nearby extracellular matrix (ECM). During ex vivo cultivation of dislocated IOL-LCs in toto, the cells proliferated and likely migrated onto the IOL's anterior side. EdU proliferation assay confirmed the proliferation potential of the myofibroblasts (MFBs) in dislocated IOL-LCs. Primary cultured lens epithelial cells/MFBs isolated from the LC of dislocated IOLs could induce collagen matrix contraction and continuously proliferated, migrated, and induced ECM remodeling. Taken together, this indicates that long-lived MFBs of dislocated IOLs might contribute to the pathogenic mechanisms in late in-the-bag IOL dislocation.

WAGRO syndrome: a rare genetic condition associated with aniridia and additional ophthalmologic abnormalities.

Aniridia is a congenital eye disorder with a variable degree of hypoplasia or absence of iris tissue. It is caused by loss of function of the PAX6 gene and may be an isolated ocular abnormality or part of a syndrome. WAGRO refers to a rare genetic condition leading to Wilms tumor, aniridia, genitourinary anomalies, mental retardation, and obesity and is caused by a deletion of the short arm of chromosome 11 (11p), where the PAX6 gene is located. Here, we report on an 8-year-old boy with aniridia, polar cataract, and lens subluxation along with neuropsychomotor and speech delays. Karyotype evaluation showed an interstitial deletion including region 11p13-p14, confirming the diagnosis of WAGRO syndrome. In cases of aniridia, a diagnosis of WAGRO syndrome should be considered.

Late-onset bilateral lens dislocation and glaucoma associated with a novel mutation in FBN1.

PURPOSE: To describe the clinical and genetic findings in one Chinese family with late-onset bilateral lens dislocation and secondary glaucoma. METHODS: One family including three affected members and 16 unaffected family members was examined clinically. After informed consent was obtained, genomic DNA was extracted from venous blood of all participants. Linkage analysis was performed with two microsatellite markers around the fibrillin-1 (FBN1) gene (D15S992 and D15S126). Mutation screening was performed using direct DNA sequence analysis and single strand conformation polymorphism (SSCP). RESULTS: Clinical examination and pedigree analysis revealed that four members in three generations were affected by late-onset lens dislocation and secondary glaucoma but had no signs of cardiovascular abnormality or abnormal skeletal features. By genotyping, the family showed the linkage to FBN1 on 15q21.1. After mutation screening analysis on 65 exons of FBN1, a novel heterozygous missense mutation, c.2860C>T (R954C), was detected. This mutation cosegregated with the disease phenotype in the family and was not found in 100 normal controls. CONCLUSIONS: Late-onset isolated ectopia lentis with secondary glaucoma is consistent with a novel mutation in FBN1. Our finding expands the spectrum of FBN1 mutations and is useful for further genetic consultation and genetic diagnosis.

Evaluation of ADAMTS17 in Chinese Shar-Pei with primary open-angle glaucoma, primary lens luxation, or both.

OBJECTIVE To evaluate the coding regions of ADAMTS17 for potential mutations in Chinese Shar-Pei with a diagnosis of primary open-angle glaucoma (POAG), primary lens luxation (PLL), or both. ANIMALS 63 Shar-Pei and 96 dogs of other breeds. PROCEDURES ADAMTS17 exon resequencing was performed on buccal mucosal DNA from 10 Shar-Pei with a diagnosis of POAG, PLL, or both (affected dogs). A candidate causal variant sequence was identified, and additional dogs (53 Shar-Pei [11 affected and 42 unaffected] and 95 dogs of other breeds) were genotyped for the variant sequence by amplified fragment length polymorphism analysis. Total RNA was extracted from ocular tissues of 1 affected Shar-Pei and 1 ophthalmologically normal Golden Retriever; ADAMTS17 cDNA was reverse transcribed and sequenced, and ADAMTS17 expression was evaluated by quantitative reverse-transcription PCR assay. RESULTS All affected Shar-Pei were homozygous for a 6-bp deletion in exon 22 of ADAMTS17 predicted to affect the resultant protein. All unaffected Shar-Pei were heterozygous or homozygous for the wild-type allele. The variant sequence was significantly associated with affected status (diagnosis of POAG, PLL, or both). All dogs of other breeds were homozygous for the wild-type allele. The cDNA sequencing confirmed presence of the expected variant mRNA sequence in ocular tissue from the affected dog only. Gene expression analysis revealed a 4.24-fold decrease in the expression of ADAMTS17 in ocular tissue from the affected dog. CONCLUSIONS AND CLINICAL RELEVANCE Results supported that the phenotype (diagnosis of POAG, PLL, or both) is an autosomal recessive trait in Shar-Pei significantly associated with the identified mutation in ADAMTS17.

Weill-Marchesani syndrome associated with retinitis pigmentosa.

Retinitis pigmentosa (RP) is associated with a wide variety of ocular and systemic disorders. The Weill-Marchesani syndrome is a multi-system disorder with microspherophakia as one of the common manifestations. A 14-year-old girl presented with short stature, short and stubby fingers, hypodontia and low-set ears. Slit-lamp examination revealed microspherophakia, with shallow anterior chambers with irido and phacodonesis. Ultrasonographic biomicroscopy confirmed the clinical findings and revealed hypoplastic ciliary body. Electroretinogram confirmed the diagnosis of RP. Though RP has been associated with ectopia lentis in earlier reports, this is, to the best of our knowledge, the first case report describing the association of RP and Weill-Marchesani syndrome.

A case of Weill-Marchesani syndrome with inversion of chromosome 15.

PURPOSE: To present a case of Weill-Marchesani syndrome with corneal endothelial dysfunction due to anterior dislocation of a spherophakic lens and corneolenticular contact. METHODS: A 17-year-old woman presented with high myopia and progressive visual disturbance. She was of short stature and had brachydactyly. Her initial Snellen best corrected visual acuity (BCVA) was 20/50 (-sph 20.50 -cyl 3.00 Ax 180) in her right eye and 20/40 (-sph 16.00 -cyl 6.00 Ax 30) in her left eye. Slit lamp examination revealed a dislocated spherophakic lens touching corenal endothelium. A microspherophakic lens, hypoplastic ciliary body, and elongated zonules were confirmed on rotating Scheimpflug camera (Pentacam) and on ultrasound biomicroscopy. Specular microscopy showed corneal endothealial dysfunction. Systemic evaluation was performed, and chromosomal study showed 46, XX, inv (15) (q13qter). The patient was diagnosed with Weill-Marchesani syndrome. RESULTS: Due to impending corneal decompensation, phacoemulsification and suture fixation of the intraocular lens were performed. The operation and postoperative course were uneventful. Three months postoperatively, the visual acuity was 20/30 (OD) and 20/40 (OS) without correction, and BCVA was 20/20 (+sph 0.50 -cyl 2.00 Ax 160 : OD) and 20/25 (+sph 1.50 -cyl 3.00 Ax 30 : OS). During the follow-up period, increased corneal endothelial counts, hexagonality, and decreased corneal thickness were achieved. CONCLUSIONS: In Weill-Marchesani syndrome with a chromosomal anomaly, a dislocated spherophakic lens may cause severe corneal endothelial dysfunction due to corneolenticular contact, and prompt lensectomy is important to prevent such complications.

Juvenile bilateral lens dislocation and glaucoma associated with a novel mutation in the fibrillin 1 gene.

PURPOSE: To describe the clinical, ocular, and genetic findings in multiple members of a family with early-onset and bilateral lens dislocation, clinical corneal guttae, and glaucoma. METHODS: All family members underwent complete physical and ophthalmic examinations. After informed consent was given, DNA was obtained from eleven family members, eight of whom were affected. Three polymorphic markers near the fibrillin 1 (FBN1) locus were genotyped and the results analyzed using the VITESSE program. Amplification of the 65 exons and flanking intronic sequences of FBN1 was performed using polymerase chain reaction (PCR), followed by conformation sensitive gel electrophoresis (CSGE). Then, all fragments with mobility variations were sequenced. RESULTS: Pedigree analysis revealed a three generation family with eight of eleven individuals affected by early onset lens dislocation, high myopia, typical facies, frontal bossing, flexion contractures, proximal interphalangeal (PIP) joint thickening, clinical corneal guttae, and glaucoma. Genetic linkage analysis using polymorphic markers near FBN1 demonstrated an LOD score of 1.78 (maximum possible LOD score 1.78). Conformation sequence gel electrophoresis analysis suggested a sequence variation in exon 3. Sequencing revealed a C965G substitution, resulting in an S322C coding change. This sequence variant segregated with affection status and was not identified in 154 control chromosomes. CONCLUSIONS: This syndrome is consistent with a novel mutation in the FBN1 gene. FBN1 mutations have been previously described as causative for Marfan syndrome. The early-onset of complete lens dislocation, progressive corneal guttae, and glaucoma is unusual for Marfan syndrome. This study expands the Marfan phenotype and demonstrates a possible link between guttae, glaucoma, and fibrillin 1 disorders.

Anterior megalophthalmos in a family with 3 female siblings.

This report describes different modes of management in 3 sisters with anterior megalophthalmos. We report our management of the anterior megalophthalmos and a new technique of anterior chamber intraocular lens implantation, which was used in 1 case.

Familial homocystinuria.

Two cases of siblings diagnosed as cases of familial homocystinuria are reported. Both the cases have classical presentation of familial homocystinuria including history of dislocation of lens of the right eye. Brother had history of psychomotor retardation while sister had a significant history of deep vein thrombosis. Levels of plasma homocysteine were elevated and urinary homocysteine was positive in both the cases.

Potential Modifying Loci Associated With Primary Lens Luxation, Pedal Hyperkeratosis, and Ocular Phenotypes in Miniature Bull Terriers.

PURPOSE: Primary lens luxation (PLL) in dogs is an inherited disease in which the lens is displaced from its normal position. A truncating mutation in the ADAMTS17 orthologue on CFA03 is reported to cause PLL in several breeds, mostly terriers. However, the complex inheritance pattern of PLL in miniature bull terriers (MBTs) suggests that other loci may have a modifying effect on the ADAMTS17 mutation. This study aimed to detect such loci increasing risk of PLL in Australian MBTs. METHODS: More than 170,000 single-nucleotide polymorphisms (SNPs) across the canine genome were genotyped in 23 PLL-affected and 73 normal Australian MBTs, and association between the PLL phenotype and the genetic markers was investigated by using general mixed effects Cox model survival analysis. RESULTS: The highest association peaks, other than that associated with the ADAMTS17 mutation (P = 2.2e-05), were SNP BICF2G630420272 located at 62.2 Mb on chromosome 15 (P = 7.8e-05) and the region between 30 Mb and 32.5 Mb on chromosome 1 (P = 9.3e-05). Joint analysis showed that the PLL-associated allele of the BICF2G630420272 SNP increased risk of PLL in the presence of the ADAMTS17 mutation (P = 8.117e-04). Candidate genes in the two regions of interest included CPE on chromosome 15 and CTGF on chromosome 1. The ADAMTS17 mutation was also associated with abnormal foot and nail shapes, pedal hyperkeratosis, and persistent pupillary membranes. CONCLUSIONS: Two loci with potentially enhancing effects on the ADAMTS17 mutation were associated with PLL in Australian MBTs. Association of the ADAMTS17 mutation with possible pedal skeletal abnormalities in MBTs supports PLL in this breed and Weill-Marchesani syndrome-like disease in humans as being homologous diseases.

Recessive mutations in LEPREL1 underlie a recognizable lens subluxation phenotype.

PURPOSE: To uncover the homozygous recessive gene mutation underlying familial lens subluxation and/or juvenile lens opacities in four sisters from a consanguineous family. METHODS: Prospective family study (clinical phenotyping; homozygosity-analysis-guided candidate gene testing). RESULTS: The proband was a 14-year-old girl with long-standing poor vision, bilateral temporal lens subluxation, lens opacities, and axial high myopia. There were no syndromic findings, and fibrillin-1 sequencing was normal. Three sisters, also non-syndromic, had undergone bilateral juvenile lens surgery (two for juvenile cataract, 1 for lens subluxation) within the first two decades of life. Both sisters who had cataract surgery developed bilateral post-operative retinal detachments and one had documented lens instability during cataract surgery. Genetic analysis revealed the phenotype to segregate with a novel homozygous recessive mutation in LEPREL1 (c.292delC; p.Gly100Alafs*104). Recessive mutations in this gene were recently highlighted as a cause for axial myopia and early-onset cataract in two families for whom some affected members also had ectopia lentis and/or post-operative retinal detachments. CONCLUSIONS: Recessive LEPREL1 mutations should be recognized as part of the differential diagnosis of lens subluxation. The associated phenotype is non-syndromic and distinguishable from other causes of ectopia lentis in the context of its additional features: juvenile lens opacities, axial myopia, and a predisposition to retinal tears/detachment following intraocular surgery.

Lens subluxation and retinal dysfunction in a girl with homozygous VSX2 mutation.

OBJECTIVE: To describe a unique lens subluxation phenotype in a child from a consanguineous family and to determine its genetic basis. METHODS: Ophthalmologic examination (including ocular biometry and electroretinography [ERG] for the proband) and autozygosity-analysis-guided exome sequencing for the family; confirmatory candidate gene sequencing in the family and ethnically matched controls. RESULTS: An otherwise healthy 3-year-old Saudi Arabian girl with poor vision since birth had smooth irides, lens subluxation, cone-rod dysfunction, and high myopia - features resembling Knobloch syndrome but differing in regard to direction of lens subluxation (superior rather than temporal) and the pattern of chorioretinal atrophy (without vitreous condensations or distinct macular atrophy). Autozygome-guided exome sequencing revealed the girl to harbor a homozygous exon 5 mutation in the ocular transcription factor gene visual homeobox 2 (VSX2) [c.773delA; p.Lys258SerfsX44] that was heterozygous in the unaffected brother and parents and absent in 100 healthy ethnically matched controls and on-line databases. Previously reported VSX2 mutations have affected the DNA-binding domains and only been associated with microphthalmia. Unlike previously reported mutations, the current VSX2 mutation is downstream to the protein's DNA binding domains. CONCLUSIONS: The phenotype of this girl is unique and suggests a normal regulatory role for VSX2 in iris, zonule, and cone-rod development. For a consanguineous family with suspected recessive ocular disease but without a clear candidate gene, autozygome-guided exome analysis is a powerful technique, even when only a single patient is affected.

Spherophakia associated with molybdenum cofactor deficiency.

Molybdenum cofactor deficiency is an autosomal recessive disorder characterized by lack of activity of the enzymes sulfite oxidase, aldehyde oxidase, and xanthine dehydrogenase or oxidase. The clinical manifestations are indistinguishable from those of isolated sulfite oxidase deficiency: craniofacial alterations, intractable neonatal convulsions, very severe mental retardation, lens dislocation, and death in the first decade of life. Lens dislocation is found in nearly all patients after neonatal age. In the present case it developed late (at the age of 8 years) and was preceded by bilateral spherophakia. We hypothesize that an abnormal relaxation of the zonular fibers is the cause of spherophakia in this disease; this causes lens dislocation eventually, after days, months, or years.

Late-onset localized junctional epidermolysis bullosa and mental retardation: a distinct autosomal recessive syndrome.

We present 2 sibs with a local junctional type of epidermolysis bullosa associated with enamel defect of the teeth, dystrophic nails of the feet, and mental retardation. Subluxation of the lenses was evident in 1 of them. This combination found in a brother and a sister seems to represent a distinct autosomal recessive type of epidermolysis bullosa.

Ectopia lentis et pupillae.

Two brothers whose parents were second cousins had ectopia lentis et pupillae. This autosomal recessive disorder is distinguished from other disorders with ectopia lentis by the limitation of abnormalities to the bilateral displacement of lens and pupil.

Bilateral megalocornea with unilateral lens subluxation.

Megalocornea refers to an enlarged cornea that measures 13 mm or more in horizontal diameter in the absence of raised intraocular pressure. We describe a five-month-old boy with bilateral megalocornea with unilateral lens subluxation. No other ophthalmological abnormality was present. In all previously reported cases with megalocornea and ectopia lentis, the lens was cataractous and the dislocation was in the inferior and posterior direction. In contrast, our case had a clear lens which was displaced superonasally.

Aniridia associated with microcornea and subluxated lenses.

Four cases of aniridia associated with subluxated lenses and microcornea are presented. The triad occurred in both eyes of the 4 affected members in one Ndebele family (one of the South African Negro tribes). No other ocular or systemic defects were noted, and intelligence was normal. Chromosomal studies on both parents showed no abnormality, and gene marker studies failed to reveal any linkage between the disease locus and a wide range of polymorphic loci.

Aetiopathological aspects of inherited lens dislocation in the Tibetan Terrier.

Four litters of Tibetan Terriers were bred in order to study the ocular pathology of primary lens luxation, which in this breed is due to an autosomal recessive gene. Scanning and transmission electron microscopy were carried out on ocular tissues of 5 dogs from 2 homozygous litters killed at various ages up to the time of onset of clinical subluxation. All eyes showed zonular abnormality, in particular a bizarre arrangement of fibrillar material associated with the ciliary processes and relating to the system of zonular fibres inserting posteriorly at the lens equator. A further litter, the result of an affected X carrier mating and killed at 20 months of age, included 2 affected and 2 unaffected dogs. The pathological changes noted in affected eyes are reconciled with the clinical signs observed in 4 homozygous dogs developing lens luxation.

Hereditary lens dislocation with angle closure glaucoma.

Eight patients in one family showed dislocation of the lens and secondary angle-closure glaucoma coming on in the 50's. They all displayed the sequence of myopia, angle shallowing, followed by angle-closure glaucoma. This sequence should alert the clinician to the possibility of a hereditary disease. The cause of the disease is unknown. It is suggested that treatment should be an iridectomy in the early stages and a lens extraction if glaucoma develops.