Randomized controlled trial on the efficacy and safety of autologous serum eye drops in dry eye syndrome.

BACKGROUND: Autologous serum eye drops (ASEDs), a novel treatment derived from blood serum, have emerged as a groundbreaking solution for managing dry eye syndrome (DES). These drops have shown significant promise in relieving the distressing symptoms of DES. This study aimed to evaluate the safety and effectiveness of ASEDs compared to traditional treatments, which often prove inadequate or result in unwanted side effects, particularly in individuals with moderate-to-severe DES. AIM: To evaluate whether ASEDs are safer and more effective than conventional artificial tears in the treatment of moderate-to-severe DES. METHODS: This multi-centered randomized controlled trial included 240 patients with moderate-to-severe DES from three ophthalmology clinics in China. They were randomly assigned to receive either ASEDs or artificial tears for 12 wk. The primary outcome was the change in the ocular surface disease index (OSDI) score, with secondary outcomes including tear break-up time (TBUT), Schirmer I test, corneal fluorescein staining (CFS), and conjunctival impression cytology (CIC). Statistics analysis was performed using an analysis of covariance with adjustments made for baseline values. RESULTS: Our findings revealed that both ASEDs and artificial tears significantly improved the OSDI score, TBUT, Schirmer I test, CFS, and CIC from baseline to week 12. The ASEDs group showed significantly greater improvement in all these measures than the artificial tears group (all P values < 0.05). The average difference in the OSDI score between the two cohorts was -10.3 (95% confidence interval: -13.6 to -7.0), indicating a substantial improvement in the ASEDs group. The occurrence of adverse events was comparable between cohorts, with no reports of severe adverse events. CONCLUSION: ASEDs are more effective and safer than artificial tears for mitigating symptoms of moderate-to-severe DES. ASEDs could be an alternative/supplementary therapy for patients with DES less responsive to traditional treatments.

Therapeutic potential of pupilloplasty combined with phacomulsification and intraocular lens implantation against uveitis-induced cataract.

AIM: To evaluate the therapeutic effect of pupilloplasty combined with phacomulsification and intraocular lens implantation (PPI) in uveitis-induced cataract. METHODS: Total 28 patients with uveitis-induced cataract were enrolled. Within 3mo before the PPI, 7 cases accompanied with glaucoma maintained carteolol hydrochloride for lowering intraocular pressure, and 1 case maintained glucocorticoid for anti-inflammation. The baseline characteristics, treatment processes, and outcomes of enrolled cases were retrospectively analyzed. Hematoxylin and eosin (HE) staining was performed to reveal the histopathological changes of iris tissues. RESULTS: Iris hemorrhage was the only intraoperative complication observed in 2 cases. After the surgery, normal intraocular pressure, right position of intraocular lens, and improved visual gain [best corrected visual acuity (BCVA)>0.5] were achieved. Postoperative keratic precipitates was observed in 2 cases, which was recovered within 1wk. During the follow-up of 5-10y, no recurrence of uveitis was found in 27 cases (96.43%). Uveitis only recurred in one case with the onset of ankylosing spondylitis. HE staining showed iris stroma (all samples), pigment cell hyperplasia in pigment epithelium (n=9) and stroma (n=19), inflammatory cell infiltration in iris (n=7), and neovascularization in iris surface (n=2). CONCLUSION: PPI improves the visual gain and prevents the long-term recurrence of uveitis in patients with uveitis-induced cataract, including those with preoperative intraocular pressure abnormality (glaucoma) and inflammation (active uveitis). Uveitis presents stroma atrophy, pigment cell hyperplasia, and inflammatory cell infiltration, even in a quiet state.

Spaceflight-associated neuro-ocular syndrome: a review of potential pathogenesis and intervention.

With the continuing progress in space exploration, a new and perplexing condition related to spaceflight ocular syndrome has emerged in the past four decades. National Aeronautics and Space Administration (NASA) has named this condition "spaceflight-associated neuro-ocular syndrome" (SANS). This article gives an overview of the current research about SANS and traditional Chinese medicine (TCM) by analyzing the existing publications on PubMed and CNKI and reports from NASA about SANS, summarizing the potential pathogenesis of SANS and physical interventions for treating SANS, and discussing the feasibility of treating SANS with TCM. Due to the unique characteristics of the space environment, it is infeasible to conduct large-scale human studies of SANS. SANS may be the result of the interaction of multiple factors, including inflammation and fluid displacement in the optic nerve sheath and cerebrospinal fluid. We should pay attention to SANS. Visual function is not only related to the health of astronauts but also closely related to space operations. TCM has antioxidative stress and antiapoptotic effects and is widely used for optic nerve diseases. TCM has great potential to prevent SANS.

[Analysis of the Related Risk Factors of Cerebral AVM Hemorrhage and the Relationship Between EPCs and SDF-1 in Brain AVM].

OBJECTIVE: To explore the related risk factors of hemorrhage in human brain cerebral arteriovenous malformations (AVM) and the relationship between endothelial progenitor cells (EPCs) content and stromal cell-derived factor-1 (SDF-1) in different ages. METHODS: A retrospective analysis was conducted on 130 patients with cerebral AVM who underwent surgical treatment from May 2012 to October 2018. Univariate and multivariate logistic analysis was used to investigate the related risk factors of cerebral AVM hemorrhage. Forty paraffin specimens of human brain AVM were harvested from 24 cases of cerebral hemorrhage patients and 16 cases of non-cerebral hemorrhage patients Paraffin samples of cerebral cortex from 8 patients with epilepsy during the same period were selected as control. Positive expression of CD34 and vascular endothelial growth factor receptor 2 (KDR2) in brain tissue samples of both groups were used to identify EPCs. Immunofluorescence double staining was used for KDR2 and CD34 positive localization to determine EPCs localization, and SDF-1 expression detection was performed. RESULTS: The size of brain AVM<3 cm, deep brain AVM and single venous drainage are independent risk factors for cerebral AVM hemorrhage. Immunohistochemical results showed that CD34 and KDR2 were expressed in cerebral AVM group, but not in the control group. Double immunofluorescence staining showed that EPCs mainly existed at the edge of vascular wall, while SDF-1 could co-stain with alpha-smooth muscle actin (α-SMA) positive cells and CD31 positive cells. SDF-1 expression in brain AVM tissue was higher than that in control group. There were significant differences in the number of EPCs among the patients of different ages ( P<0.05). There was no significant difference in EPCs between cerebral hemorrhage group and non-hemorrhage group ( P>0.05). CONCLUSION: Brain AVM (<3 cm), single venous drainage and deep brain AVM are independent risk factors for cerebral AVM hemorrhage. In human brain AVM, EPC appears high level but decrease with age, which may play a role in vascular remodeling in AVM.

Recurrent PAX 6 mutation in a Chinese family with congenital aniridia, progressive cataracts and mental retardation.

BACKGROUND: One prominent pathological feature of congenital aniridia is hypoplasia of the iris, often accompanied by other eye abnormalities. The objective of this study is to identify gene mutations responsible for autosomal dominance in a Chinese family with congenital aniridia, progressive cataracts and mental retardation. METHODS: A total of 11 family members, including 6 affected and 5 unaffected individuals were recruited. Whole exome sequencing was performed on the proband and Sanger sequencing was applied to identify the causal mutation in the other family members and control samples. RESULTS: A heterozygous mutation, c. 112delC (p. Arg38fs) in PAX 6, was identified in the family that was associated with congenital aniridia, progressive cataracts and mental retardation. The mutation was exclusively observed in all affected individuals but not in unaffected family members or unrelated healthy controls without aniridia recruited from Beijing Tongren Hospital. Bioinformatics analysis indicated that the mutation c. 112delC (p. Arg38fs) in PAX 6 affected sugar phosphate backbone construction, leading to half reduction of the full-length protein. Other symptoms such as lens opacity, keratitis, lens dislocation, ciliary body hypoplasia, foveal hypoplasia and mental development retardation were also observed in this family. CONCLUSION: These results provided a new insight into the effects of PAX 6 as a mutational hotspot, with a symptom complex that includes congenital aniridia, progressive cataracts and mental retardation. These findings suggested the cognitive treatment of PAX 6-mutated individuals could be considered earlier clinically, combined with medication or surgery of congenital aniridia and progressive cataracts.

Characterization of a p.R76H mutation in Cx50 identified in a Chinese family with congenital nuclear cataract.

BACKGROUND/PURPOSE: A three-generation Chinese family with autosomal dominant congenital nuclear cataract was recruited. This study aimed to identify the disease-causing gene for nuclear cataract with functional dissections of the identified mutant. METHODS: Detailed clinical data and family history were recorded. Candidate gene sequencing was performed to identify the disease-causing mutation. Recombinant connexin50 (Cx50) wild type and mutant constructs were synthesized. Triton X-100 solubility and subcellular localization of the recombinant Cx50 proteins were analyzed in HeLa cells. Apoptosis was assayed as the percentage of fragmented nuclei in transfected cells. RESULTS: All affected individuals in the family displayed clear phenotypes of dense nuclear cataracts. A c.227 G > A variation was found in the coding region of Cx50, which arginine residue at position 76 was substituted by histidine (p.R76H). This mutation was co-segregated with the disease in the family, and was not observed in 110 unrelated Chinese controls. No statistically significant differences were found in the Triton X-100 solubility and apoptosis rate between wild type and mutant Cx50 in HeLa cells. However, Cx50 mutant was unable to form gap junctional plaques between adjacent cells as the wild type proteins did. CONCLUSION: This study identified a novel cataract phenotype caused by the p.R76H mutation in Cx50, providing evidence of further phenotypic heterogeneity associated with this mutation. Functional analysis showed that the mutation affected the formation of gap junction channels and led to opacity in the lens.

Mutation Analysis of Families with Autosomal Dominant Congenital Cataract: A Recurrent Mutation in the CRYBA1/A3 Gene Causing Congenital Nuclear Cataract.

PURPOSE: To identify the CRYBA1/A3 mutation spectrum and analyze the genotype-phenotype correlations in Chinese families with congenital cataract. METHODS: Family history and clinical data of 47 unrelated families with autosomal dominant congenital cataract (ADCC) were recorded. CRYBA1/A3 gene sequencing was applied to identify the causative mutation. Haplotypes were constructed using closely linked microsatellite markers and intragenic single-nucleotide polymorphisms (SNPs) to compare the affected haplotype in three families. RESULTS: Nuclear cataract was the most common type of ADCC in Chinese families, accounting for 42.6% (20/47). A recurrent CRYBA1/A3 deletion mutation (ΔG91) was identified in three families (6.4%) with nonprogressive nuclear congenital cataract. Different haplotypes segregated with the mutation in each family. CONCLUSIONS: A recurrent ΔG91CRYBA1/A3 mutation occurs independently in 6.4% of the Chinese families with autosomal dominant nuclear cataracts and most likely represents a mutational hot spot, which underscores the relations between nonprogressive nuclear cataract and CRYBA1/A3.

Photothermal Ring Integrated Intraocular Lens for High-Efficient Eye Disease Treatment.

Posterior capsule opacification (PCO) is the most common complication after cataract surgery. So far, the only method for PCO treatment is the precisely focused laser surgery. However, it causes severe complications such as physical damages and neuron impairments. Here, a nanostructured photothermal ring integrated intraocular lens (Nano-IOLs) is reported, in which the rim of commercially available IOLs (C-IOLs) is decorated with silica coated Au nanorods (Au@SiO2 ), for high-efficient prevention of PCO after cataract surgery. The Nano-IOLs is capable of eliminating the residual lens epithelial cells (LECs) around Nano-IOLs under mild laser treatment and block the formation of disordered LECs fibrosis, which eventually leads to the loss of vision. The Nano-IOLs shows good biocompatibility as well as extraordinary region-confined photothermal effect. In vivo studies reveal that PCO occurrence in rabbit models is about 30%-40% by using Nano-IOLs, which is significantly lower than the control group that treated with C-IOLs (100% PCO occurrence) 30 d postsurgery. To the best of our knowledge, it is the first example to integrate nanotechnology with intraocular implants aiming to clinically relevant PCO. Our findings indicate that spatial controllability of photothermal effect from nanomaterials may provide a unique way to intervene the PCO-induced loss of vision.

Mutation analysis in Chinese families with autosomal dominant hereditary cataracts.

PURPOSE: To identify the molecular basis and clinical phenotype in three Chinese families with hereditary cataracts. METHODS: Detailed family history and clinical data were recorded. The phenotypes were documented using slit-lamp photography. Candidate genes sequencing was performed to screen out the disease causing mutation. Bioinformatics analysis was performed to predict the function of mutant genes. RESULTS: The phenotypes of the families were identified as nuclear cataract in Family 1, pulverulent cataract in Family 2, and nuclear cataract in Family 3. Direct sequencing revealed transversions of C > T at c.218 (p. S73F) in GJA8 in Family 1, A > C at c.125 (p. E42A) in GJA3 in Family 2, and C > T at c.268 (p. L90F) in GJA3 in Family 3. These mutations co-segregated with all affected individuals in the family and were not found in unaffected family members nor in the 100 unrelated controls. Bioinformatics analysis indicated that S73F in GJA8, E42A and L90F in GJA3 are highly conserved. S73F in GJA8, E42A and L90F in GJA3 could possibly be damaging predicted by PolyPhen-2, with score of 0.858, 1.000, 1.000, respectively. CONCLUSIONS: This study identified three mutations in three Chinese families with hereditary cataracts. Of the three mutations, two were novel (c.125 A > C in GJA3 and c.268 C > T in GJA3), one was previously reported (c.218 C > T in GJA8).

A novel p.G112E mutation in BFSP2 associated with autosomal dominant pulverulent cataract with sutural opacities.

PURPOSE: To identify the genetic defect in a Chinese family with bilateral pulverulent sutural cataract. MATERIALS AND METHODS: A three-generation family with congenital cataract was recruited in the study. The study protocol followed the principles of the Declaration of Helsinki. Detailed family history and clinical data were recorded. Genomic DNA was extracted from peripheral blood leukocytes. Candidate gene sequencing was performed to identify the disease-causing mutation. The effects of amino acid changes on the structure and function of proteins were predicted by bioinformatics analysis. RESULTS: All affected individuals presented pulverulent opacities in the embryonal nucleus and sutures. Direct candidate gene sequencing revealed a heterozygous c. 335 G>A variation in the beaded filament structural protein 2(BFSP2) gene, which resulted in the replacement of a highly conserved glycine by glutamic at codon 112 (p. G112E). Haplotype analysis indicated that the affected members shared a common haplotype with markers near BFSP2. This mutation co-segregated with all affected individuals and was not observed in unaffected members or in 120 ethnically matched controls. Bioinformatic analyses confirmed that the mutation altered the hydrophobic and secondary structure of the protein around the substitution site. CONCLUSIONS: We report a novel mutation (p.G112E) in the BFSP2 gene, underscoring the physiological importance of the beaded filament protein and supporting its role in human cataract formation.

[Detection of differentially expressed lumican gene mRNA level in scleral tissue in human eye].

OBJECTIVE: To identify differentially expressed lumican in scleral tissue of eyes with primary open-angle glaucoma (POAG) and high myopia (HM). METHODS: Total RNA was isolated from scleral tissue of cadaveric eyes derived from normal donors, patient's eyes with diagnosed glaucoma and high myopia who accepted trabeculectomy. RNA was amplified, RT-PCR was used to measure the levels of mRNA. The ratio of the electrophoresis strips'gray scale values of the ß-actin over the lumican gene was obtained for ANOVA analysis. RESULTS: ß-actin/LUM of normal eye was significantly higher than that of POAG and POAG + HM eyes (P < 0.01), but there was no significant difference between POAG and POAG + HM eyes (P > 0.05). CONCLUSIONS: Differentially expressed lumican between POAG and control groups identified in this study have not been previously investigated for their role in the pathogenesis of POAG and thus are novel factors for further study of the mechanism of the disease and for their possible use as diagnostic markers.

A novel p.F206I mutation in Cx46 associated with autosomal dominant congenital cataract.

PURPOSE: To identify the genetic defect in a Chinese family with bilateral congenital cataract. METHODS: A three-generation family was recruited in this study. Detailed family history and clinical data were recorded. Ten candidate genes were screened for causative mutations. Direct sequencing was performed to analyze the cosegregation of the genotype with the disease phenotype. RESULTS: Affected individuals presented embryonal nuclear opacities in the lens. Sequencing of the candidate genes showed a heterozygous c. 616T>A variation in the connexin 46 (Cx46) gene, which resulted in the replacement of a highly conserved phenylalanine by isoleucine at codon 206 (p. F206I). This mutation co-segregated with all affected individuals and was not observed in unaffected family members or ethnically matched controls. CONCLUSIONS: We report a novel mutation (p.F206I) in the fourth transmembrane domain of connexin 46. These findings thus expand the mutation spectrum of Cx46 in association with congenital cataract.

Identification of the p. R116H mutation in a Chinese family with novel variable cataract phenotype: evidence for a mutational hot spot in αA-crystallin gene.

PURPOSE: To report the recurrent p.R116H mutation in the αA-crystallin gene (CRYAA) which causes a novel variable cataract phenotype, and to determine whether this mutation represents a mutational hot spot. METHODS: Family history and clinical data were recorded. The genomic DNA was extracted from peripheral blood leukocytes. Microsatellite markers at loci considered to be associated with autosomal dominant cataracts were selected and genotyped for two-point linkage analysis. Direct sequencing was performed to identify the disease-causing mutation. Haplotype analysis was constructed to compare the affected haplotype in this family and in another Chinese family previously reported by us. RESULTS: Clinical features of cataract in this family were asymmetric in two eyes of some affected subjects. Evidence of linkage was obtained with marker D21S1411 (logarithm of odds [LOD] score [Z] = 2.42, recombination fraction [θ] = 0.0). Sequencing of the candidate CRYAA gene revealed a single base alteration c.347 G > A in exon 3, which resulted in the substitution of highly conserved arginine by histidine at codon 116 (p.R116H). This mutation co-segregated with all affected individuals and was not observed in unaffected family members or 100 normal unrelated individuals. The comparative haplotype analysis showed that the affected haplotypes in the two families were different. CONCLUSIONS: This study identified a novel cataract-microcornea phenotype caused by the recurrent mutation p.R116H in CRYAA, and suggested that this mutation site is not likely the consequence of a founder effect, but probably a result of a mutational hot spot.

Rigid iris-fixated phakic lens implantation for high myopia: novel trapezoidal corneal versus scleral incisions.

PURPOSE: To compare refractive performance of implantation of an iris-fixated phakic intraocular lens (PIOL) through a novel trapezoidal corneal and a scleral tunnel incision. METHODS: Sixty-nine eyes selected to undergo PIOL implantation were randomly assigned to 1 of 2 groups: 5.2-mm trapezoidal corneal incision (TCI), 34 eyes; 5.2-mm scleral tunnel incision (STI), 35 eyes. Visual acuity, refraction, corneal astigmatism, tonometry, and endothelial cell density were recorded preoperatively and postoperatively. Surgically induced astigmatism (SIA) was calculated using vector analysis. RESULTS: No intraoperative complications were noted. One day after surgery, the quantity of cells in the anterior chamber was significantly lower in TCI group than in STI group (p=0.019). The percentage of eyes with uncorrected visual acuity (UCVA) of ≥20/25 was 41.2% for TCI and 17.1% for STI; the difference was statistically significant (p=0.03), but not thereafter. The mean corneal astigmatism was significantly lower in the TCI group than in the STI group (p=0.01) 3 months postoperatively and subsequently. No significant between-group difference in SIA was found during the follow-up. There was no significant difference in best-corrected visual acuity and endothelial cell loss between groups, postoperatively. CONCLUSIONS: The TCI and STI techniques are comparable in terms of safety and induction of astigmatism for the rigid iris-fixated PIOL implantation. However, the TCI is easy to perform and provides a faster visual recovery and lower postoperative corneal astigmatism compared with the STI.

A novel mutation in CRYBB1 associated with congenital cataract-microcornea syndrome: the p.Ser129Arg mutation destabilizes the ßB1/ßA3-crystallin heteromer but not the ßB1-crystallin homomer.

Congenital cataract-microcornea syndrome (CCMC) is a clinically and genetically heterogeneous condition characterized by lens opacities and microcornea. It appears as a distinct phenotype of heritable congenital cataract. Here we report a large Chinese family with autosomal dominant congenital cataract and microcornea. Evidence for linkage was detected at marker D22S1167 (LOD score [Z]=4.49, recombination fraction [θ]=0.0), which closely flanks the â-crystallin gene cluster locus. Direct sequencing of the candidate âB1-crystallin gene (CRYBB1) revealed a c.387C>A transversion in exon 4, which cosegregated with the disease in the family and resulted in the substitution of serine by arginine at codon 129 (p.Ser129Arg). A comparison of the biophysical properties of the recombinant ß-crystallins revealed that the mutation impaired the structures of both ßB1-crystallin homomer and ßB1/ßA3-crystallin heteromer. More importantly, the mutation significantly decreased the thermal stability of ßB1/ßA3-crystallin but not ßB1-crystallin. These findings highlight the importance of protein-protein interactions among ß-crystallins in maintaining lens transparency, and provide a novel insight into the molecular mechanism underlying the pathogenesis of human CCMC.

The association of a single nucleotide polymorphism in the promoter region of the LAMA1 gene with susceptibility to Chinese high myopia.

PURPOSE: High myopia is a severe hereditary ocular disease leading to blindness. LAMA1 (alpha subunit of laminin) is a promising candidate gene for high myopia present in the MYP2 (myopia 2) region. The purpose of this study was to determine if high myopia is associated with single nucleotide polymorphism (SNP) variants in LAMA1 in Chinese subjects. METHODS: Ninety-seven Chinese subjects with high myopia and ethnically and sexually matched 103 normal controls were enrolled. Genomic DNA was prepared from peripheral blood. The 5 SNPs of LAMA1 were analyzed using PCR and SNaPshot. Allele frequencies were tested for Hardy-Weinberg disequilibrium. The genotype and allele frequencies were evaluated using the χ(2) tests or the Fisher exact tests. RESULTS: One of the 5 SNPs showed a significant difference between patients and control subjects (rs2089760: p(genotype)=0.005, p(allel)=0.003). There were no statistically significant differences between patients and control subjects for the other four SNPs: rs566655, rs11664063, rs607230, and rs3810046. CONCLUSIONS: Our results indicate that the polymorphism of rs2089760, located in the promoter region of LAMA1, may be associated with high myopia in the Chinese population and should be investigated further.

Novel beta-crystallin gene mutations in Chinese families with nuclear cataracts.

OBJECTIVE: To investigate the molecular genetic background in families with nuclear congenital cataract. METHODS: Family history and clinical data were recorded. Ten candidate genes were screened for causative mutations. Direct sequencing was performed to analyze the cosegregation of the genotype with the disease phenotype. Effects of amino acid changes on the structure and function of protein were predicted by bioinformatics analysis. RESULTS: Analyses of 20 Chinese families with hereditary nuclear congenital cataract revealed 3 novel mutations. Two of these mutations (V146M and I21N) affected ßB2-crystallin (CRYBB2). One mutation (R233H) was detected in ßB1-crystallin (CRYBB1). These mutations cosegregated with all affected individuals and were not observed in unaffected family members or the 150 healthy unrelated individuals. CONCLUSIONS: The CRYBB2 gene was shown to be another causative gene associated with congenital cataract and microcornea. Three novel mutations in ß-crystallin genes (CRYB) were detected in Chinese families with nuclear autosomal dominant congenital cataracts, which underscores the genetic heterogeneity of this condition. CLINICAL RELEVANCE: Studying the genetics of nuclear cataracts is helpful for better understanding the pathophysiologic mechanisms that underlie this phenotype and for better disease management. This study helps expand the genotype of nuclear cataract and microcornea.

A novel mutation in MIP associated with congenital nuclear cataract in a Chinese family.

PURPOSE: To identify the underlying genetic defect in a Chinese family affected with autosomal dominant congenital nuclear cataract. METHODS: A four-generation Chinese family with inherited nuclear cataract phenotype was recruited. Detailed family history and clinical data were recorded. All reported nuclear cataract-related candidate genes were screened for causative mutations by direct DNA sequencing. Effects of amino acid changes on the structure and function of protein were predicted by bioinformatics analysis. RESULTS: All affected individuals in this family showed nuclear cataracts. Sequencing of the candidate genes revealed a heterozygous c.559C>T change in the coding region of the major intrinsic protein (MIP), which caused a substitution of highly conserved arginine by cysteine at codon 187 (p.R187C). This mutation co-segregated with all affected individuals and was not observed in unaffected family members or 110 ethnically matched controls. Bioinformatics analysis showed that the mutation was predicted to affect the function and secondary structure of MIP protein. CONCLUSIONS: This study identified a novel disease-causing mutation p.R187C in MIP in a Chinese cataract family, expanding the mutation spectrum of MIP causing congenital cataract.

[Progress in pathogenic genes and their functions of congenital cataract].

Congenital cataract is the common cause of visual disability in children. Inherited isolated (non-syndromic) cataract represents one third of cases. Currently, at least 22 specific genes associated with isolated inherited cataract have been identified: ten crystallin genes: CRYAA, CRYAB, CRYBA1/A3, CRYBA4, CRYBB1, CRYBB2, CRYBB3, CRYGC, CRYGD, CRYGS; 4 membrane protein genes: GJA3, GJA8, MIP, LIM2; three growth and transcription factor genes: PITX3, MAF, HSF4; two cytoskeletal protein gene: BSFP1, BSFP2; chromatin modifying protein-4B gene: CHMP4B, EPHA2 and NHS, it is likely that more genes remain to be discovered. Some of the genes have been studied for their function by expression in cells or/and by knock-out animal models. The increasing availability of more detailed information about their functions makes it possible to understand the pathophysiology of congenital cataracts.

Autosomal dominant congenital nuclear cataracts caused by a CRYAA gene mutation.

PURPOSE: We sought to identify the genetic defect in a four-generation Chinese family with autosomal dominant congenital nuclear cataracts, examine the clinical features in detail and demonstrate the functional analysis of a candidate gene in the family. METHODS: Family history data were recorded. Clinical and ophthalmological examinations were performed on affected and unaffected family members. All the members were genotyped with microsatellite markers at loci considered to be associated with cataracts. Two-point LOD scores were calculated using the LINKAGE program package after genotyping. A mutation was detected by dilff521229rect sequencing and verified by denaturing high-performance liquid chromatography (DHPLC). Wild-type and mutant proteins were analyzed with online softwares. RESULTS: All affected members of this family had nuclear cataracts. Genetic analysis revealed a heterozygous previously described Arg116Cys mutation in the CRYAA gene in all of the affected members of the family but not in unaffected or 100 normal, unrelated individuals. Data generated with online software revealed that the different amino acid side chain, impact the aa116 interaction with other amino acids, thereby affecting the proteins secondary structure. CONCLUSIONS: This study identified a mutation in the CRYAA gene causing autosomal dominant nuclear cataracts and some patients show nystagmus or small blepharophimosis clinical features. These results provide evidence that CRYAA is a pathogenic gene for congenital cataracts, congenital cataracts are a clinically and genetically heterogeneous lens condition; at the same time, demonstrates a possible mechanism of action for the mutant gene.