Clinical and Genetic Landscape of Ectopia Lentis Based on a Cohort of Patients From 156 Families.

Purpose: To extend the mutation spectrum and explore the characteristics of genotypes and ocular phenotypes in ectopia lentis (EL). Methods: Variants in all 14 reported EL-associated genes were selected from in-house data sets as well as literature review, and available clinical data were analyzed. Results: Likely pathogenic variants in three genes were identified in 156 unrelated families with EL from the in-house cohort, of which 97.4% resulted from variants in FBN1, whereas the remaining were caused by variants in ADAMTSL4 (1.3%) and LTBP2 (1.3%). A comparative analysis of the in-house data and literature review suggested several characteristics: (1) a higher proportion of cysteine involvement variants in FBN1, either variants introducing or eliminating cysteine, and an earlier diagnosis age were presented in our cohort than in published literature; (2) the axial length (AL) and refractive error increased more rapidly with age in preschool EL children than normal children, and the increased rate of AL was slower in patients with surgery than those without surgery; (3) aberrant astigmatism was common in EL; and (4) worse vision and earlier onset age were observed in patients with non-FBN1 variants (all P < 0.05). Conclusions: Variants in FBN1 are the predominant cause of EL, with the most common cysteine involvement variants. Early-stage EL manifests refractive error but gradually converts to axial myopia through defocus introduced by lens dislocation. Aberrant astigmatism is a suggestive sign of EL. Non-FBN1 variants cause early-onset and severe phenotypes. These results provide evidence for early diagnosis as well as timely treatment for EL.

Uncovering the Hidden World of Aqueous Humor Proteins for Discovery of Biomarkers for Marfan Syndrome.

Ectopia lentis is a hallmark of Marfan syndrome (MFS), a genetic connective tissue disorder affecting 1/5000 to 1/10 000 individuals worldwide. Early detection in ophthalmology clinics and timely intervention of cardiovascular complications can be lifesaving. In this study, a modified proteomics workflow with liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based data-independent acquisition (DIA) and field asymmetric ion mobility spectrometry (FAIMS) to profile the proteomes of aqueous humor (AH) and lens tissue from MFS children with ectopia lentis is utilized. Over 2300 and 2938 comparable proteins are identified in AH and the lens capsule, respectively. Functional enrichment analyses uncovered dysregulation of complement and coagulation-related pathways, collagen binding, and cell adhesion in MFS. Through weighted correlation network analysis (WGCNA) and machine learning, distinct modules associated with clinical traits are constructed and a unique biomarker panel (Q14376, Q99972, P02760, Q07507; gene names: GALE, MYOC, AMBP, DPT) is defined. These biomarkers are further validated using advanced parallel reaction monitoring (PRM) in an independent patient cohort. The results provide novel insights into the proteome characterization of ectopia lentis and offer a promising approach for developing a valuable biomarker panel to aid in the early diagnosis of Marfan syndrome via AH proteome.

A novel ADAMTSL4 compound heterozygous mutation in isolated ectopia lentis: a case report and review of the literature.

BACKGROUND: Congenital ectopia lentis is characterized by dislocation of the lens caused by partial or complete abnormalities in the zonular fibers. It can be caused by either systemic diseases or isolated ocular diseases. Gene detection techniques can provide valuable information when an etiological diagnosis is challenging. Herein, we report the case of a six-year-old girl with a confirmed diagnosis of isolated ectopia lentis caused by a compound heterozygous ADAMTSL4 gene mutation. CASE PRESENTATION: The patient was a 6-year-old Chinese Han girl with strabismus in the right eye. Slit lamp examination revealed that the lens in the right eye was opacified and dislocated, without an ectopic pupil. Gene detection demonstrated the presence of a compound heterozygous mutation in the ADAMTSL4 gene [c. 2270dupG (p.Gly758Trpfs *59) and c. 2110A > G (p.Ser704Gly)], and the diagnosis of isolated ectopia lentis was confirmed. She underwent lens extraction, and a sutured scleral-fixated posterior chamber intraocular lens (IOL) was placed in the right eye. The best-corrected visual acuity was 0.1 one month postoperatively. CONCLUSION: Gene detection plays a crucial role in diagnosing disorders with similar symptoms, such as isolated ectopia lentis and Marfan syndrome. In this study, we used whole exons sequencing to diagnose isolated ectopia lentis and identified the variant c.2110A > G (p.Ser704Gly), which may be associated with the development of ectopia lentis and early-onset cataract in the patient. These pathogenic gene mutations have significant implications for the genetic diagnosis of congenital ectopia lentis, treatment, surveillance, and hereditary and prenatal counseling for the patient and their family members.

Evaluation of functional vision and eye-related quality of life in children with congenital ectopia lentis: a prospective cross-sectional study.

OBJECTIVES: This study aims to evaluate the effect of congenital ectopia lentis (CEL) on functional vision and eye-related quality of life (ER-QOL) in children and their families using the Paediatric Eye Questionnaire (PedEyeQ). DESIGN: A questionnaire survey administered via in-person interviews of patients with CEL and their parents. PARTICIPANTS: 51 children with CEL and 53 visually normal controls accompanied by 1 parent completed the survey questionnaires for the study from March 2022 to September 2022. OUTCOME MEASURES: PedEyeQ domain scores. Functional vision and ER-QOL of children and their families were evaluated by calculating and comparing the Rasch domain scores of the PedEyeQ. RESULTS: PedEyeQ domain scores were significantly worse with CEL compared with controls (p<0.01 for each), with the exception of the Proxy Social domain among children aged 0-4 years (p=0.283). Child PedEyeQ greatest differences were in the functional vision domain (5-11 years, -20 points (95% CI -27 to -12)) and frustration/worry domain (12-17 years, -41 (95% CI -37 to -6)). Proxy PedEyeQ greatest differences were in the functional vision domain (0-4 years, -34 (95% CI -45 to -22)) and frustration/worry domain (5-11 years, -27 (95% CI -39 to -14); 12-17 years, -37(95% CI (-48 to -26))). Parent PedEyeQ greatest difference was in the 'worry about child's eye condition' (-57 (95% CI (-63 to -51))). CONCLUSIONS: In this study, children with CEL had reduced functional vision and ER-QOL compared with controls. Parents of children with CEL also experience reduced quality of life.

Incidence and de novo mutation rate of Marfan syndrome and risk of ectopia lentis.

PURPOSE: To investigate the population-based incidence and de novo mutation rate of Marfan syndrome and risk of ectopia lentis. METHODS: Patients newly diagnosed with Marfan syndrome in Olmsted County, Minnesota, from January 1, 1976, through December 31, 2005, were identified through medical records review. Outcome measures were Marfan incidence, de novo mutation rate, risk of ectopia lentis. RESULTS: Marfan syndrome was identified in 17 patients during the 30-year period, yielding an incidence of 0.52 per 100,000 people/year (95% CI, 0.27-0.77). Mean age at diagnosis was 24.4 years (range, 1.7 year to 51.3 years). Nine patients (53%) were female. Of the 17, 5 (29%) were new mutations, with a calculated mutation rate of 3.8 ± 1.7 × 10-5. Four (24%) were diagnosed with ectopia lentis, including 3 at the time of their Marfan diagnosis. Of the 14 patients at risk for developing ectopia lentis after being diagnosed with Marfan syndrome, 1 (7%) developed it during a mean follow-up of 9 years (range, 0-6.4). Twelve (71%) were diagnosed with dilated ascending aorta during a mean follow-up of 13.2 years (range, 6.7 months to 28.9 years). CONCLUSIONS: Incidence and de novo mutation rate of Marfan syndrome in this population-based cohort was higher than prior reports. Ectopia lentis, whose prevalence in North America has not been reported previously, occurred in approximately one-fourth of study patients and more commonly around the time of initial Marfan diagnosis.

Characteristics and genotype-phenotype correlations in ADAMTS17 mutation-related Weill-Marchesani syndrome.

Weill-Marchesani syndrome (WMS) manifests as ectopia lentis (EL), microspherophakia and short stature, which is caused by ADAMTS10, LTBP2, or ADAMTS17 gene defects. This study aims to investigate the characteristics and genotype-phenotype correlations of WMS with ADAMTS17 mutations. WMS patients with ADAMTS17 variants were identified by whole-exome sequencing from 185 patients with EL. All the included patients underwent comprehensive ocular and systemic examinations. ADAMTS17 variants were reviewed from included patients, published literature, and public databases. Bioinformatics analysis, co-segregation analysis, species sequence analysis, and protein silico modeling were used to verify the pathogenic mutations. A total of six novel ADAMTS17 mutations (c.1297C > T, c.2948C > T, c.1322+2T > C, c.1716C > G, c.1630G > A, and c.1669C > T) were identified in four WMS probands in our EL cohort (4/185, 2.16%). All probands and their biological parents presented with apparent short stature compared with the standard value. In particular, one child was detected with valvular heart disease, which has not previously been reported in patients with ADAMTS17 mutations. Conserved residues were greatly affected by the substitution of amino acids caused by these six mutations. Short stature could be considered a clue for EL patients with ADAMTS17 mutations, and much more attention needs to be paid to heart disorders among these patients. This study not only reported the characteristics of ADAMTS17 mutation-related WMS but also helped to recognize the genotype-phenotype correlations in these patients.

Traboulsi syndrome without features of Marfan syndrome caused by a novel homozygous ASPH variant associated with a heterozygous FBN1 variant.

BACKGROUND: Traboulsi syndrome is a rare disease clinically characterized by facial dysmorphism, abnormal spontaneous filtering blebs, ectopia lentis (EL) and multiple anterior segment abnormalities. MATERIAL AND METHODS: An 18-year-old female was referred to the Emergency Service of Hospital São Geraldo (HSG) claiming decreased right eye (RE) visual acuity associated with ocular pain that was noticed approximately 2 months earlier. She underwent a complete ophthalmic and physical examination including hands, ankle, wrist and chest X-ray, abdominal ultrasound, echocardiogram and genetic analysis (whole-exome sequencing). RESULTS: The ophthalmic examination revealed a high myopia with spherical equivalent of - 9.50 D and best corrected visual acuity (BCVA) of 20/60 in RE and - 9.25 D with BCVA of 20/30 in the left eye (LE). Slit-lamp examination showed normal conjunctiva in both eyes (BE) and a superior-temporal cystic lesion in RE and nasal in LE; the flat anterior chamber in BE with the transparent crystalline lens touches the central corneal endothelium in the RE. Fundoscopy suggested glaucoma as the cup/disc ratio was 0.7, although the intraocular pressure (IOP) was 10 mmHg in BE without medication. Validation of data from whole exome demonstrated a novel splicing homozygous pathogenic variant (PV) (c.1765-1G>A) of the ASPH gene as well as a heterozygous variant of unknown significance (VUS) of the FBN1 gene (c.6832C>T). CONCLUSION: We here report a novel splice-affecting homozygous pathogenic variant in the ASPH gene that was detected in a Brazilian patient with clinical features of Traboulsi syndrome.

The Role of Genetic Testing in Children Requiring Surgery for Ectopia Lentis.

Non-traumatic ectopia lentis can be isolated or herald an underlying multisystemic disorder. Technological advances have revolutionized genetic testing for many ophthalmic disorders, and this study aims to provide insights into the clinical utility of genetic analysis in paediatric ectopia lentis. Children that underwent lens extraction for ectopia lentis between 2013 and 2017 were identified, and gene panel testing findings and surgical outcomes were collected. Overall, 10/11 cases received a probable molecular diagnosis. Genetic variants were identified in four genes: FBN1 (associated with Marfan syndrome and cardiovascular complications; n = 6), ADAMTSL4 (associated with non-syndromic ectopia lentis; n = 2), LTBP2 (n = 1) and ASPH (n = 1). Parents appeared unaffected in 6/11 cases; the initial presentation of all six of these children was to an ophthalmologist, and only 2/6 had FBN1 variants. Notably, 4/11 cases required surgery before the age of 4 years, and only one of these children carried an FBN1 variant. In summary, in this retrospective cohort study, panel-based genetic testing pointed to a molecular diagnosis in >90% of paediatric ectopia lentis cases requiring surgery. In a subset of study participants, genetic analysis revealed changes in genes that have not been linked to extraocular manifestations and highlighted that extensive systemic investigations were not required in these individuals. We propose the introduction of genetic testing early in the diagnostic pathway in children with ectopia lentis.

Zonule-Associated Gene Variants in Isolated Ectopia Lentis and Glaucoma.

PRCIS: We report 3 novel variants in fibrillin-1 (FBN1) and latent transforming growth factor-ß-binding protein 2 (LTBP2) in 3 families with isolated ectopia lentis (EL), which shed new light on the diagnosis and genetic counseling of EL and secondary glaucoma in clinical settings. PURPOSE: To explore the genetic mechanism in 3 families with isolated EL and secondary angle closure glaucoma. METHODS: Three Han Chinese families with EL and glaucoma were recruited. All of the participants underwent complete ocular and general physical examinations and DNA samples were extracted from peripheral venous blood and screened for disease-causing variants using whole exome and Sanger sequencing. In silico analyses were performed to predict the structural and functional changes in gene variants and abnormal proteins. RESULTS: All 3 probands presented with EL and pupillary-blocking glaucoma. Genetic testing showed that all the patients have zonule-related gene mutations, with the proband (II:1), as well as his mother (I:2) and daughters (III:1 and III:2) from family 1 carrying a heterozygous mutation in FBN1 gene (c.6493G>T:p.(V2165L)); the proband (II:1) from family 2 carrying a heterozygous mutation in FBN1 gene (c.2543C>A:p.(T848N)), and the proband (II:1) from family 3 carrying a pair of compound heterozygous mutations in LTBP2 gene (c.4825T>A:p.(C1609S) / c.529T>C:p.(W177R)). No other genetic variants were found to be associated with the phenotypes of patients and other family members in this study. All variants are predicted to affect the structure and function of proteins as risk factors for EL based on bioinformatics analysis. CONCLUSION: Four novel mutations were identified in 3 families with EL, suggesting an intimate link between specific mutations in FBN1 and LTBP2 and isolated EL and angle closure glaucoma. Our results expanded the variant spectrum of zonule-related genes and helped explore the underlying molecular pathology of these disorders.

Clinical and genetic findings in Chinese families with congenital ectopia lentis.

BACKGROUND: Congenital ectopia lentis (EL) refers to the congenital dysplasia or weakness of the lens suspensory ligament, resulting in an abnormal position of the crystalline lens, which can appear as isolated EL or as an ocular manifestation of a syndrome, such as the Marfan syndrome. The fibrillin-1 protein encoded by the FBN1 gene is an essential component of the lens zonules. Mutations in FBN1 are the leading causes of congenital EL and Marfan syndrome. Owing to the complexity and individual heterogeneity of FBN1 gene mutations, the correlation between FBN1 mutation characteristics and various clinical phenotypes remains unclear. METHODS: This study describes the clinical characteristics and identifies possible causative genes in eight families with Marfan syndrome or isolated EL using Sanger and whole-exome sequencing. RESULTS: Eight FBN1 mutations were identified in these families, of which three (c.5065G > C, c.1600 T > A, and c.2210G > C) are reported for the first time. Based on in silico analyses, we hypothesized that these mutations may be pathogenic by affecting the fibrillin-1 protein structure and function. CONCLUSION: These findings expand the number of known mutations involved in EL and provide a reference for the research on their genotype and phenotype associations.

Metabolomic Profile in the Aqueous Humor of Congenital Ectopia Lentis.

PURPOSE: To explore the metabolic profiles in the aqueous humor (AH) of patients with congenital ectopia lentis (CEL). METHODS: We conducted a comprehensive analysis of the metabolites of AH samples of patients with CEL (n = 22) and age-matched patients (n = 22) with congenital cataract by ultra-high performance liquid chromatography tandem-mass spectrometry. The metabolomic characteristics were visualized by principal component analysis, orthogonal partial least squares discriminant analysis and heat map. The levels of the differential metabolites were also compared between CEL patients with and without FBN1 mutations. Pathway enrichment analysis was performed by using Kyoto Encyclopedia of Genes and Genomes. Receiver operating characteristic analysis was performed to select potential biomarkers. RESULTS: There were 175 differential metabolites identified between the two groups. Eight metabolites were found to be potential biomarkers in AH of CEL patients. The CEL group showed a significant increase in α-ketoglutarate and decrease in citrate, suggesting that the tricarboxylic acid (TCA) cycle was disturbed. l-proline, prolyl-hydroxyproline, and l-histidine were reduced, which prompted enhanced degradation of microfibrils and collagen. Insidious retinal nerve damage was implied because N-Acetyl-aspartylglutamic acid and N-Acetyl-l-aspartic acid were found to be significantly increased. Pathway enrichment analysis indicated that disturbances in amino acid metabolism and carbohydrate metabolism were the key processes in the pathogenesis of CEL and that TCA cycle disorder may be the driving force behind disease occurrence. CONCLUSION: These data reveal the characteristics in the metabolomic profiles of the AH of CEL patients, which help provide insights into the pathogenesis of this rare disease.

Novel ADAMTSL4 gene mutations in Chinese patients with isolated ectopia lentis.

BACKGROUND: To characterise the phenotype and genetic defects of isolated ectopia lentis (IEL) and to determine the ADAMTSL4 gene mutation frequencies in a Chinese congenital ectopia lentis (CEL) cohort. METHODS: In total, 127 Chinese probands with a clinical CEL diagnosis were recruited for this study and underwent ocular and systemic examinations. Whole-exome sequencing was used to detect variants, and Sanger sequencing and bioinformatics analysis verified the pathogenic mutations. RESULTS: Overall, biallelic mutations in ADAMTSL4, involving 8 novel ADAMTSL4 mutations (c.21-2A>G, c.1174G>C, c.2169C>A, c.2236C>T, c.2263delG, c.2397C>A, c.2488dupC and c.2935T>C) were identified in 5 probands (5/127, 3.94%) with IEL. Additionally, four patients had combined congenital cataracts, and two patients had ectopia lentis et pupillae (ELP). One of eight mutations was a homozygous missense mutation, and the other seven mutations were compound heterozygous. These eight consisted of three missense (37.5%), three frameshift (37.5%), one stop-gain (12.5%) and one spicing mutation (12.5%). These mutations co-segregated with the IEL, and the substitution of amino acids greatly affected conserved residues. Most of the novel mutations were located in the thrombospondin type 1 (TSP1) domain, which ultimately alters the structure of the ADAMTSL4 protein. CONCLUSIONS: This study reported five IEL probands with eight novel mutations in the ADAMTSL4 gene. The clinical IEL phenotypes caused by these mutations were variable and complex. This study thus establishes the ADAMTSL4 gene mutation frequency and expands the gene's mutation spectrum to help recognise ADAMTSL4-related IEL clinical manifestations.

Identification and phenotypic analysis of novel LTBP2 mutations in a Chinese cohort with congenital ectopia lentis.

Purpose: To evaluate the frequency of LTBP2 mutations and to elaborate on LTBP2-related clinical phenotypes in a Chinese congenital ectopia lentis (CEL) cohort. Methods: In total, 145 Chinese probands with CEL were recruited for this study and underwent ocular and systemic examinations. Whole-exome sequencing was used to identify mutations, and Sanger sequencing and bioinformatics analysis were further performed to verify pathogenic mutations. Results: Overall, biallelic mutations in LTBP2 involving eight novel mutations (c.4370-7_4370-9delTCT, c.4370-5C>G, c.3452G>A, c.2253delG, c.4114T>C, c.1251G>A, c.4760G>A, and c.620G>A) were identified in four CEL probands (4/145, 2.76%). Patients with LTBP2 mutations were characterized by a megalocornea, spherophakia, high myopia, and glaucoma instead of a flat cornea, high corneal astigmatism, cardiovascular and skeletal abnormalities that were reported in other gene mutations. A novel homozygous frameshift mutation was detected, and this type of mutation was found to cause more complicated ocular symptoms than others, ranging from the anterior segment to the fundus. Conclusion: This study reported the mutation frequency of the LTBP2 gene in a Chinese CEL cohort and provided novel insight into LTBP2-related genotype-phenotype associations in CEL.

Epidemiology of ectopia lentis and outcomes after surgery in a Danish population.

PURPOSE: To describe the causes of ectopia lentis (EL) and the outcomes after surgery in a Danish population. SETTING: The Eye Clinic Rigshospitalet and Kennedy Center in Copenhagen. DESIGN: Retrospective cohort study. METHODS: Medical records of patients with nontraumatic EL born after 1980 and seen at the Eye Clinic Rigshospitalet and Kennedy Center from 1983 to 2019 were reviewed. Clinical information regarding family history, comorbidities, genetic workup, ophthalmological examinations, and surgical history was retrieved. RESULTS: 72 patients (38 males), of whom 68 had bilateral EL (94.4%) were identified. Marfan syndrome (MFS) was found in 34 (47.2%) and biallelic variants in ADAMTSL4 in 4 (5.6%). Surgery was performed in 38 (52.8%) patients, 66 eyes, with a median age at the time of first eye surgery of 8.4 years (range 0.8 to 39.0 years) and a follow-up of 2.3 years (range 0 to 25.7 years). Intraocular lenses were implanted in 9 (23.7%) (11 eyes). Corrected distance visual acuity improved from 0.7 to 0.2 logMAR (median) in right eyes and from 0.7 to 0.3 logMAR in left eyes postoperatively. 21 patients (56.8%), 42 eyes, did not experience any surgery-related complications. 3 patients (3 eyes) experienced a perioperative tear in the posterior capsule. Temporary postoperative ocular hypertension was reported in 3 patients (7.9%) (3 eyes), and 2 patients (5.4%) (2 eyes) developed persistent ocular hypertension. There were no cases of postoperative retinal detachment. CONCLUSIONS: The main reason for EL was MFS. Surgery improved visual acuity, and postoperative ocular hypertension was the most common complication, whereas retinal detachment was not observed.

Biallelic ADAMTSL4 variants in a Chinese cohort of congenital ectopia lentis: Implications for genotype-phenotype relationships.

ADAMTSL4 variants are one of the common causes of congenital ectopia lentis (EL), reported ocular comorbidities of which include iris anomalies, cataract, and glaucoma. However, a genotype-phenotype correlation has not been established. Potentially pathogenic ADAMTSL4 variants were screened from a Chinese cohort of congenital EL using panel-based next-generation sequencing followed by multiple bioinformatics analyses. The genotype-phenotype correlation was assessed via a systematic review of ADAMTSL4 variants within our data and those from the literature. A total of 12 variants of ADAMTSL4, including seven frameshift variants, one nonsense variant, two splicing variants, and two missense variants, were found in nine probands. Combing genetic and clinical information from 72 probands in the literature revealed 37 ADAMTSL4 variants known to cause EL, and the ethnic difference was prominent. The lens was inclined to dislocate inferior temporally (22, 27.16%), while the pupil was always located oppositely (9, 81.82%). Several anterior segments anomalies were identified, including ectopia pupillae (15, 18.52%), persistent pupillary membrane (9, 11.10%), poor pupil dilation (4, 30.8%), cataract (13, 24.10%), and glaucoma (8, 13.33%). Genotype-phenotype analysis revealed that truncation variants had higher risks of combined iris anomalies, including either ectopia pupillae or a persistent pupillary membrane (p = 0.007). The data from this study not only extend our knowledge of the ADAMTSL4 variant spectrum but also suggest that deleterious variants of ADAMTSL4 might be associated with severe ocular phenotypes.

The phenotypic spectrum of ADAMTSL4-associated ectopia lentis: Additional cases, complications, and review of literature.

Purpose: ADAMTSL4-associated ectopia lentis is a rare autosomal recessive condition that is primarily associated with crystalline lens displacement. However, the prevalence of other ocular and systemic manifestations of this condition is poorly understood. In this study, we summarize the ocular and systemic phenotypic spectrum of this condition. Methods: A cross-sectional case study series of four individuals with biallelic pathogenic or likely pathogenic ADAMTSL4 variants was performed alongside a literature review of individuals with ADAMTSL4-associated ectopia lentis on September 29, 2021. Ocular and systemic findings, complications, and genetic findings of all four individuals were collected and summarized. Results: The phenotypic spectrum across 91 individuals sourced from literature and four individuals from this case study series was highly variable. The main ocular phenotypes included ectopia lentis (95/95, 100%), ectopia lentis et pupillae (18/95, 19%), iris transillumination (13/95, 14%), iridodonesis (12/95, 13%), persistent pupillary membrane (12/95, 13%), and early-onset cataract or lens opacities (12/95, 13%). Anterior segment features other than ectopia lentis appeared to be exclusively associated with biallelic loss of function variants (p<0.001). Pupillary block glaucoma had a prevalence of 1%. Post-lensectomy complications included retinal detachment (6/41, 15%), elevated intraocular pressure (4/41, 10%), and aphakic glaucoma (1/41, 2%). Most individuals were not reported to have had systemic features (69/95, 73%). Conclusions: The clinical phenotype of ADAMTSL4-associated ectopia lentis was summarized and expanded. Clinicians should be aware of the varied ocular phenotype and the risks of retinal detachment, ocular hypertension, and glaucoma in the diagnosis and management of this condition.

Early Onset Marfan Syndrome with multivalvular insufficiency: Report from a tertiary hospital in Tanzania, and a review of the recurrent c.7606G>A p.0 variant in FBN1.

Marfan Syndrome is an autosomal dominant connective tissue disorder caused by mutations in the FBN1 gene. Early Onset Marfan Syndrome is at the severe end of the Marfan syndrome spectrum and is frequently associated with variants in exons 24-32 of the FBN1 gene. To the best of our knowledge, this is the first molecularly confirmed patient from Sub-Saharan Africa with Early Onset Marfan Syndrome who presented with tall stature, arachnodactyly, multivalvular insufficiency and ectopia lentis. Sequencing analysis of FBN1 gene revealed a pathogenic (class 5) heterozygous recurrent variant in exon 61 (c.7606G > A p.0NM_000138.3), which was up to now not associated with rapidly progressive Marfan syndrome with multivalvular insufficiency and congestive cardiac failure. This further supports the notion that the interplay of the given FBN1 mutation, one or more genetic modifiers and epigenetic and environmental factors defines the disease phenotype.

Correlation between novel compound heterozygous ADAMTSL4 variants and primary phenotypes of ectopia lentis et pupillae.

PURPOSE: To investigate molecular pathogenesis of congenital ectopia lentis accompanied by various ophthalmic manifestations in a pedigree. METHODS: Three female siblings, their spouse and offspring underwent ophthalmic and general medical examinations. Genetic variants were screened with the whole exome sequencing and analyzed in either a dominant or recessive inheritance manner. Gene mutations were ascertained with the Sanger sequencing after the polymerase chain reaction. RESULTS: All three female siblings were diagnosed as the Ectopia lentis et pupillae (ELeP) through combination of clinical examination and genetic analysis. No characteristic pathological changes of skeletal, metabolic and cardiac abnormalities were observed. Thirteen genetic variants were selected out through analyzing in the dominant or recessive inheritance manner, but they were not associated with EL. Among them, ALOX15B variant may explain the skin disease in this pedigree. After inspection the known genes related to EL, novel compound heterozygous mutations (p.Ser264LeufsX37/p.Gly757ValfsX62) in ADAMTSL4 were discreetly identified in this ELeP pedigree. CONCLUSIONS: Novel compound heterozygous ADAMTSL4 variants are responsible for ELeP in the current pedigree. Correlation between ADAMTSL4 variants and ELeP was firstly established based on our 12 years follow-up studies and previous reports of ELeP and of ADAMTSL4-related eye disorders. The primary phenotypes caused by ADAMTSL4 variants include EL, EP, poor pupillary dilation, and axial elongation. Highly varying phenotypes including glaucoma, high myopia retinapathy, and poor vision and so on may be the secondary impairments. All these secondary impairments may be improved if proper clinical interventions are implemented in time.

Next-generation sequencing panel analysis in 24 Chinese patients with congenital ectopia lentis.

BACKGROUND: Congenital ectopia lentis (CEL) is a rare but serious disease. We use next-generation sequencing to detect genes associated with lens abnormalities in 24 patients with bilateral CEL and search for pathogenic genes and mutation sites. MATERIALS AND METHODS: A total of 24 patients diagnosed with CEL from January 2019 to November 2019 were enrolled in this study, and their clinical data were collected and genome-wide deoxyribonucleic acid was extracted from peripheral venous blood. Targeted gene capture technology was used to obtain 188 exons of lens abnormality-related genes, which were sequenced using a high-throughput method. The mutation sites were determined through data analysis and verified by the Sanger method. According to the data from previous studies, the association between the genotype and clinical phenotype was analysed. RESULT: Of the 24 patients, 23 had mutations in the fibrillin-1 (FBN1) gene, and 20 were diagnosed with Marfan syndrome. The 23 cases of FBN1 mutations were all heterozygous mutations, including 17 missense mutations, 3 splicing variants, 2 exon deletion mutations, 1 codon mutation, and 9 new mutations. A total of 17 mutations were located in the calcium-binding epidermal growth factor domain, including 16 mutations that contained missense mutations of cysteine. In addition, a heterozygous mutation of the gap junction protein alpha 8 (GJA8) gene was detected in one patient. CONCLUSION: In this study, we identified 23 FBN1 gene mutations and 1 GJA8 gene mutation in 24 patients with CEL. Of these, 9 new FBN1 mutations and 14 known mutations were found. The results expanded the mutation spectrum of the FBN1 gene, suggesting that FBN1 mutation may be the main cause of CEL in Chinese patients.