Association of variants in the ATXN2 (rs7137828), FOXC1 (rs2745572) and TXNRD2 (rs35934224) genes as risk factors for primary open-angle glaucoma development in a Brazilian cohort.

BACKGROUND: Primary open-angle glaucoma (POAG), the world's main cause of irreversible blindness, is an asymptomatic and neurodegenerative disease of multifactorial etiology with ethnic and geographic disparities. Multiethnic genome-wide association studies (GWAS) identified single nucleotide variants (SNVs) in ATXN2, FOXC1, and TXNRD2 loci as risk factors for POAG pathophysiology and/or endophenotypes. The aim of this case-control study was to investigate the association of the variants rs7137828 (ATXN2), rs2745572 (FOXC1), and rs35934224 (TXNRD2), as risk factors for POAG development, additionally to rs7137828 association with glaucoma clinical parameters in a Brazilian cohort from the Southeast and South regions. METHODS: This investigation comprised 506 cases and 501 controls. Variants rs2745572 and rs35934224 were genotyped through TaqMan® assays and validated by Sanger sequencing. Variant rs7137828 was genotyped exclusively by Sanger sequencing. RESULTS: The primary research outcome revealed that the variant rs7137828 (ATXN2) was associated with an increased risk for the development of POAG in the presence of the TT genotype compared to the CC genotype (p = 0.006; Odds Ratio [OR] = 1.717; Confidence Interval [CI] 95% = 1.169-2.535). There was no significant association of rs2745572 and rs35934224 genotypes with POAG. The CT genotype of the rs7137828 was associated with the vertical cup-to-disk ratio (VCDR) (p = .023) but not with the age at diagnosis or the mean deviation. CONCLUSION: Our data indicate the rs7137828 associated with increased risk for the development of POAG and VCDR in a Brazilian cohort. If validated in additional populations, these findings may enable the development of relevant strategies for early diagnosis of glaucoma in the future.

Association of ABCA1 (rs2472493) and GAS7 (rs9913911) gene variants with primary open-angle glaucoma in a Brazilian population.

Purpose: Glaucoma is the world's leading cause of irreversible blindness, with primary open-angle glaucoma (POAG) being the most prevalent subtype. In recent years, there have been advances in knowledge about the genetics involved in POAG, but genetic studies in admixed populations, such as Brazilians, are still rare. This study aimed to evaluate the association of single nucleotide variants (SNV) of the ABCA1 (rs2472493) and GAS7 (rs9913911) genes with POAG in a sample of the Brazilian population. Furthermore, the study aimed to evaluate the relationship between these SNVs and the need for surgical intervention in glaucoma control. Methods: A cross-sectional association study with 1,009 subjects (505 patients with POAG and 504 controls) was performed. Participants underwent a comprehensive ocular examination, including the need for surgical procedures for intraocular pressure control. Genotyping of SNVs was performed using the TaqMan genotyping assay. Results: SNV rs9913911 of GAS7 was found to be associated with POAG in the presence of the risk allele A (p = 0.0004) and the AA genotype (p = 0.002). There was no association between SNV rs2472493 of ABCA1 for either the allele risk or genotypes. However, the combination of these variants showed an additive effect on the risk for POAG: ABCA1(GG) + GAS7(AA; p = 0.02), ABCA1(GG) + GAS7(AG; p = 0.003), and ABCA1(AG) + GAS7(AG; p = 0.004). Also, POAG patients carrying the AA genotype of the GAS7 gene required antiglaucomatous surgery more frequently than those without the AA genotype (p = 0.01). Conclusions: In a Brazilian population sample, there was an association identified between SNV rs9913911 (GAS7) and the risk of POAG, and an additive effect was found when GAS7 was combined with SNV rs2472493 (ABCA1). There was an association between SNV rs9913911 (GAS7) and the risk for antiglaucomatous surgery.

Bruch's membrane opening - minimum rim width measurement after acute primary angle-closure.

PURPOSE: To evaluate Bruch's membrane opening - minimum rim width (BMO-MRW) and peripapillary retinal nerve fiber layer thickness (RNFLT) following an acute primary angle-closure attack (APAC). MATERIALS AND METHODS: Nine consecutive patients with unilateral APAC were included. Patients with a bilateral attack, with signs of glaucomatous optic nerve damage or evidence of a previous APAC in either eye were excluded. Three months after the attack, all eyes underwent BMO-MRW and RNFLT measurements with SDOCT. APAC eyes were compared to the contralateral eyes. RESULTS: Three months after the attack, mean BMO-MRWs were 281.22 ± 56.88 µm and 313.78 ± 43.48 µm (P = 0.009) and mean RNFLTs were 78 ± 15.36 µm vs 95.78 ± 10.81 µm (P = 0.008) in the APAC and contralateral eyes, respectively. RNFLT and BMO-MRW measurements had a strong positive correlation (R = 0.7436, P = 0.013). APAC eyes had a shorter axial length (21.85 ± 1.21 vs 22 ± 1.07, P = 0.042) and shallower anterior chamber depth (2.29 ± 0.21 vs 2.41 ± 0.12, P = 0.039) than contralateral eyes. IOP at presentation showed a strong negative correlation with both BMO-MRW (R = -0.7669, P = 0.009) and RNFLT measurements (R = -0.7723, P = 0.008). CONCLUSION: BMO-MRW and RNFLT measurements are significantly reduced 3 months after an APAC when compared to the contralateral eye. IOP at presentation may have an impact on the reduction of these parameters.

Corneal Scheimpflug topography values to distinguish between normal eyes, ocular allergy, and keratoconus in children.

To identify and compare keratometric, corneal thickness, and elevation parameters and indices among healthy children, ocular allergy, and keratoconus using the OCULUS Pentacam Scheimpflug topography system. This study included healthy children, children with ocular allergy (OA) without keratoconus, and children with keratoconus (KC). The study design consisted of a prospective evaluation and review of medical records from a Brazilian ophthalmology department. The exclusion criteria were inability to undergo the ocular exam, other ocular diseases, contact lens wear, and topographic corneal ectasia. The effect of each corneal parameter was evaluated using univariate and multivariate logistic regression models adjusted for sex and age, and ROC curves were used to assess the ability each variable to discriminate among groups. A total of 182 subjects were included: healthy children (n = 99), children with OA (n = 32), and children with KC (n = 51). Groups differed in terms of sex, with more males in the OA group (73.2%) and the KC group (67.7%) than in the control group (40.9%). All corneal parameters studied differed significantly between the control and KC groups, and between the OA and KC groups; they also differed significantly between the three groups in terms of astigmatism, q-value, CCT, TP, BAD-D, and ARTmax values. We present the first study to describe and compare corneal tomographic parameters in healthy children, OA, and KC. Keratometry indices, ACD, ARTmax, AETP, and PETP were found to be the most useful for differentiating between healthy and KC children.IBR registry number: CAAE 54921916.9.0000.5404.

Comparison of conventional and wide field direct ophthalmoscopy on medical students' self-confidence for fundus examination: a 1-year follow-up.

BACKGROUND: Fundus examination is an easy, quick and effective way to diagnose sight- and life-threatening diseases. However, medical students and physicians report lack of proficiency and self-confidence in perform fundoscopy. The aim of this study was to compare students' self-confidence in fundus examination, using two different direct ophthalmoscopes, 1 month and 1 year after practical training. METHODS: In this prospective cohort, medical students (MS) of the same class were divided in small groups for PanOptic (PO) or conventional (CO) direct ophthalmoscope training. The intervention group encompassed MS of the 4th -year (class of 2019), and the control group encompassed MS of year behind (class of 2020). A questionnaire to measure self-confidence in fundoscopy technique assessing optic nerve, cup-to-disc ratio and macula was translated and validated to Portuguese, and applied 1-month and 1-year after practical training. RESULTS: One-hundred and sixty-seven MS were enrolled (35 PO group, 38 CO group, and 94 control group). PO group had a significantly higher overall self-confidence comparing either control or CO groups, respectively (3.57 ± 0.65 vs. 2.97 ± 1.03 vs. 2.46 ± 0.87, p < 0.01) as well as in evaluate cup-to-disc ratio (3.09 ± 0.75 vs. 2.32 ± 0.87 vs. 1.46 ± 0.81, p < 0.01), optic disc margins (3.26 ± 0.85 vs. 2.71 ± 0.96 vs. 2.01 ± 0.97, p < 0.01) and macula (3.43 ± 1.12 vs. 2.89 ± 1.08 vs. 2.02 ± 0.89, p < 0.01) 1-month after practical training. One-year after intervention, CO group showed a significantly higher score compared to PO group in overall self-confidence (3.31 ± 0.69 vs. 3.18 ± 0.73, p = 0.03) and in optic disc margins assessing (3.16 ± 0.85 vs. 2.95 ± 0.78, p = 0.03), but not significant in the evaluation of cup-to-disc ratio (2.78 ± 0.97 vs. 2.68 ± 0.94, p = 0.08), and macula (3.34 ± 0.79 vs. 3.27 ± 0.98, p = 0.07). CONCLUSIONS: Students were more confident in use PO as an instrument to perform direct ophthalmoscopy immediately after practical training, but confidence level of CO was higher compared to PO one year after practical training. These findings would help medical schools decide which ophthalmoscope to choose to teach fundus examination.

The effects of age-related macular degeneration on quality of life in a Brazilian population.

BACKGROUND: To evaluate the impact of age-related macular degeneration (AMD) on the quality of life (QoL) in a Brazilian population using The National Eye Institute-Visual Function Questionnaire-25 (NEI-VFQ-25). METHODS: This observational study included 462 participants from the Departments of Ophthalmology of the University of Campinas and Conderg-Divinolândia. The NEI-VFQ-25 questionnaire and Rasch analysis were used to assess the vision-related quality of life (VRQoL). Patients with macular neovascularization were interviewed at enrollment and after three loading doses of intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment. RESULTS: One hundred thirty-three patients were excluded because they had another ophthalmic disease, for a total of 349 patients included in the study (177 in the AMD group, 172 in the control group; 56.4% were women; mean ± standard deviation age, 70.6 ± 9.5 years). Most NEI-VFQ-25 subscale scores were significantly lower in the AMD group compared with the control group. The Rasch-calibrated NEI-VFQ-25 median score in the visual-functioning component was 56.41 for the AMD group and 61.53 for the control group, a difference of ± 4.00 (P = 0.0001). Separate analyses of the sociodemographic and ocular characteristics showed that the NEI-VFQ-25 scores were affected mostly by family income, educational level, descent, diet (vegetables/fruits), physical activity, and visual acuity (VA). The longitudinal component assessed a different group of 48 patients with exudative disease treated with anti-VEGF drugs. The mean logarithm of the minimum angle of resolution change in VA in treated eyes was a 0.16 decrease (P = 0.01). The mean change in the optical coherence tomography macular thickness was a 36.74-µm decrease (P = 0.012) from baseline to 4 months. The mean NEI-VFQ-25 scores improved significantly from baseline to follow-up at 4 months in almost all subscales. CONCLUSIONS: In a Brazilian community, patients with AMD had a worse VRQoL than controls. The AMD severity and bilaterality were associated with decreased NEI-VFQ-25 scores. Higher family income, educational level, descent, and lifestyle significantly improved several subscales of the NEI-VFQ-25 questionnaire. Treated patients with exudative AMD had improvements in the VA, macular thickness, and most NEI-VFQ-25 subscale scores.

Occurrence of MYOC and CYP1B1 variants in juvenile open angle glaucoma Brazilian patients.

BACKGROUND: The purpose of this study was to screen juvenile open angle glaucoma (JOAG) patients from Brazil for variants within the MYOC and CYP1B1 genes. MATERIAL AND METHODS: In this study, we evaluated the coding regions of MYOC and CYP1B1 genes in 100 non-related patients with JOAG and 200 controls through Sanger sequencing. We also tested the most frequent single nucleotide variants of CYP1B1 for association with JOAG. RESULTS: Sixteen different sequence variants in the MYOC gene were observed in JOAG patients: eight variants were described as neutral and eight were identified in 34 out of 100 patients with JOAG and no controls, thus being considered damaging. In the CYP1B1 gene, nine neutral variants and two damaging alterations were found among JOAG patients. No association between CYP1B1 variants and JOAG was detected. CONCLUSION: While MYOC damaging alterations were highly prevalent (34%), CYP1B1 damaging variants were less frequent (2%) in this cohort of Brazilian JOAG patients.

Estimating the age of the p.Cys433Arg variant in the MYOC gene in patients with primary open-angle glaucoma.

The aim of this study was to estimate the age of the Cys433Arg (c.1297T>C, p.Cys433Arg) variant by comparing the genotypes of individuals affected and not affected by primary open angle glaucoma juvenile onset (JOAG). Our sample consisted of 35 JOAG-affected individuals from three families, 16 unrelated patients with the MYOC p.Cys433Arg variant and 16 unaffected individuals. Genomic DNA was amplified by PCR; nine short tandem repeats were genotyped through automated electrophoresis and three single nucleotide polymorphisms through Sanger sequencing. The determination of haplotypes was performed using Arlequin software and age estimation was performed using DMLE+ 2.3 and BDMC21 softwares. Four markers constituted the haplotypes associated with the p.Cys433Arg variant. The software DMLE+2.3 predicted an age of 43 generations for this variant with a 95% confidence interval ranging from 28 to 76 generations (560-1520 years) and BDMC21 predicted an age of 59 generations (1180 years) (95% CI: 40 to 100).

Association of HTRA1 rs11200638 with age-related macular degeneration (AMD) in Brazilian patients.

Age-related macular degeneration is a multifactorial disease that can lead to vision impairment in older individuals. Although the etiology of age-related macular degeneration remains unknown, risk factors include age, ethnicity, smoking, hypertension, obesity, and genetic factors. Two main loci have been identified through genome-wide association studies, on chromosomes 1 and 10. Among the variants located at the 10q26 region, rs11200638, located at the HTRA1 gene promoter, has been associated with age-related macular degeneration in several populations and is considered the main polymorphism. We conducted a replication case-control study to analyze the frequency and participation of rs11200638 in the etiology of age-related macular degeneration in a sample of patients and controls from the State of São Paulo, Brazil, through polymerase chain reaction and enzymatic digestion. The frequency of the A allele was 57.60% in patients with age-related macular degeneration and 36.45% in controls (p value < 1e-07), representing a 2.369-fold higher risk factor for the disease. Both the AA and AG genotypes were observed more frequently in the age-related macular degeneration group compared to the control group (p = 1.21e-07 and 0.0357, respectively). No statistically significant results were observed after stratification in dry versus wet types or advanced versus non-advanced forms. To our knowledge, this is the first time the association between rs11200638 and overall age-related macular degeneration has been reported in South America.

Investigation of CAV1/CAV2 rs4236601 and CDKN2B-AS1 rs2157719 in primary open-angle glaucoma patients from Brazil.

Large-scale genome-wide association studies have identified several susceptibility variants associated with the risk of primary open-angle glaucoma (POAG), among which rs4236601 (CAV1/CAV2) at chromosome 7q31 and rs2157719 at chromosome 9p21 (CDKN2B-AS1). The purpose of this study was to investigate whether these variants contribute to the incidence of POAG in a sample of the Brazilian Southeastern population and to determine the best-fitted genetic model for these single nucleotide polymorphisms (SNPs). A case-control study with 557 individuals, 310 with POAG, and 247 controls was conducted through PCR and direct sequencing. We observed a significant effect of the heterozygous genotype (G/A) of rs2157719 that occurred more frequently in the control group (p = 0.0004; OR: 0.517, CI 95%: 0.357-0.745). Allele frequencies also differed between cases and controls (p = 0.006; OR: 0.694, CI 95%: 0.522-0.922) with the best-fitted genetic model for rs2157719 being the codominant model. No differences were observed for genotype and allele distributions in relation to rs4236601 in the CAV1/CAV2 region. The association of rs2157719 (CDKN2B-AS1) with the POAG phenotype corroborates previously published results, reinforcing the importance of this variant in POAG etiology.

Differentiating Leber Hereditary Optic Neuropathy from Normal-Tension Glaucoma.

Glaucoma is a neurodegenerative disorder characterized by thinning of neuroretinal rim, enlarged cup-to-disc ratio (CDR) and visual field damage. Although raised intraocular pressure is main risk factor for development of glaucoma, it can occur with consistently normal measurements in the intraocular pressure as normal tension glaucoma (NTG). Enlargement of CDR is a classical sign of glaucoma, but it can also result from non-glaucomatous optic neuropathies such as Leber hereditary optic neuropathy (LHON). We describe a case of LHON with increased CDR, discuss its differential diagnosis with NTG and highlight the reasons for misdiagnoses between these two entities.

Genotype-Phenotype Correlations in CYP1B1-Associated Primary Congenital Glaucoma Patients Representing Two Large Cohorts from India and Brazil.

BACKGROUND: Primary congenital glaucoma (PCG), occurs due to the developmental defects in the trabecular meshwork and anterior chamber angle in children. PCG exhibits genetic heterogeneity and the CYP1B1 gene has been widely implicated worldwide. Despite the diverse mutation spectra, the clinical implications of these mutations are yet unclear. The present study attempted to delineate the clinical profile of PCG in the background of CYP1B1 mutations from a large cohort of 901 subjects from India (n=601) and Brazil (n=300). METHODS: Genotype-phenotype correlations was undertaken on clinically well characterized PCG cases from India (n=301) and Brazil (n=150) to assess the contributions of CYP1B1 mutation on a set of demographic and clinical parameters. The demographic (gender, and history of consanguinity) and quantitative clinical (presenting intraocular pressure [IOP] and corneal diameter [CD]) parameters were considered as binary and continuous variables, respectively, for PCG patients in the background of the overall mutation spectra and also with respect to the prevalent mutations in India (R368H) and Brazil (4340delG). All these variables were fitted in a multivariate logistic regression model using the Akaike Information Criterion (AIC) to estimate the adjusted odds ratio (OR) using the R software (version 2.14.1). RESULTS: The overall mutation spectrum were similar across the Indian and Brazilian PCG cases, despite significantly higher number of homozygous mutations in the former (p=0.024) and compound heterozygous mutations in the later (p=0.012). A wide allelic heterogeneity was observed and only 6 mutations were infrequently shared between these two populations. The adjusted ORs for the binary (demographic) and continuous (clinical) variables did not indicate any susceptibility to the observed mutations (p>0.05). CONCLUSIONS: The present study demonstrated a lack of genotype-phenotype correlation of the demographic and clinical traits to CYP1B1 mutations in PCG at presentation. However, the susceptibility of these mutations to the long-term progression of these traits are yet to be deciphered.

Association of LOC387715/ARMS2 (rs10490924) Gene Polymorphism with Age-Related Macular Degeneration in the Brazilian Population.

BACKGROUND: An association between LOC387715/ARMS2 (rs10490924) gene polymorphism and AMD has been reported. The aim of this study was to evaluate whether this polymorphism is associated with AMD in a Brazilian cohort. MATERIALS AND METHODS: In total, 126 unrelated AMD patients (mean age 74.17 ± 7.64) were compared with 86 healthy controls (mean age 71.82 ± 7.12). Study subjects were classified according to the International ARM Epidemiological Study Group definition for early and late-stage AMD. LOC387715/ARMS2 rs10490924 polymorphism was evaluated through polymerase chain reaction and direct sequencing. RESULTS: The T allele frequency was significantly higher in AMD patients than in controls (39.6% compared to 20.3%). The odds ratio (OR) for AMD was 2.05 (95% CI 1.13-3.71) for heterozygotes (TG) and 8.32 (95% CI 2.30-45.99) for homozygotes (TT). CONCLUSIONS: These results suggest that there is a contribution of the rs10490924 SNP of the LOC387715/ARMS2 gene to AMD susceptibility in this sample of the Brazilian population.

New mutation in the myocilin gene segregates with juvenile-onset open-angle glaucoma in a Brazilian family.

Mutations in the myocilin gene (MYOC) account for most cases of autosomal dominant juvenile-onset open-angle glaucoma (JOAG), an earlier and more severe form of POAG. We accessed seven members of a Brazilian JOAG family by clinical and molecular investigation. Four out of seven family members were diagnosed with JOAG. All of these patients presented high intraocular pressure and two of them were bilaterally blind. The disease onset varied from 20 to 30years old. There was a nine-year-old family member who had not yet manifested the disease, although he was also a carrier of the mutation. Ophthalmologic examination included: evaluation of the visual field and optic disc, intraocular pressure measurement, and gonioscopy. The three exons and intron/exon junctions of the MYOC gene were screened for mutations through direct sequencing of PCR-amplified DNA fragments. Mutation screening revealed an in-frame mutation in the third exon of the MYOC gene: an insertion of six nucleotides between the cDNA positions 1187 and 1188 (c.1187_1188insCCCAGA, p.D395_E396insDP). This mutation presented an autosomal dominant pattern of inheritance, segregating with the disease in four family members for three generations, and it was absent in 60 normal controls. We also performed a computational structure modeling of olfactomedin-like domain of myocilin protein and conducted in silico analysis to predict the structural changes in the myocilin protein due to the presence of the mutation. These findings may be important for future diagnosis of other presymptomatic family members, as well as for the increase of the panel of MYOC mutations and their effects on phenotype.

Evaluation of the efficacy and safety of botulinum toxin type A to induce temporary ptosis in dogs.

PURPOSE: To verify the safety and efficacy of botulinum toxin type A (BoNT/A) to promote protective ptosis in dogs. METHODS: In this prospective interventional study, a total of 10 dogs underwent transcutaneous anterior chemodenervation of levator palpebral superioris with 15 U of BoNT/A. The systemic changes, ocular mobility, visual function, intraocular pressure (IOP), tear production, and the onset, degree, and duration of ptosis were evaluated on a daily basis during the first 7 days and on days 14, 21, and 28 after application. RESULTS: The onset of the clinical effect was observed between 2 and 3 days after application of the toxin; the time taken for maximum ptosis to develop varied from 4 to 7 days (mean 5 days) and the average duration of the toxin effect was 21 days. The mean percentage reduction in palpebral fissure height was 42.859% (SD±35.714%-59.821%). There was not a statistically significant difference in IOP before and after the BoNT/A application (P=0.974), or lacrimal production evaluation (P=0.276). There was no change in ocular mobility and no other adverse effect was observed in association with the administration of the study drug. CONCLUSION: The application of BoNT/A into the levator palpebral superioris muscle in dogs was effective and safe to promote protective ptosis with a temporary covering of the cornea.

Novel human CRYGD rare variant in a Brazilian family with congenital cataract.

PURPOSE: To describe a novel polymorphism in the γD-crystallin (CRYGD) gene in a Brazilian family with congenital cataract. METHODS: A Brazilian four-generation family was analyzed. The proband had bilateral lamellar cataract and the phenotypes were classified by slit lamp examination. Genomic DNA was extracted from peripheral blood and coding regions and intron/exon boundaries of the αA-crystallin (CRYAA), γC-crystallin (CRYGC), and CRYGD genes were amplified by polymerase chain reaction and directly sequenced. RESULTS: Sequencing of the coding regions of CRYGD showed the presence of a heterozygous A→G transversion at c.401 position, which results in the substitution of a tyrosine to a cysteine (Y134C). The polymorphism was identified in three individuals, two affected and one unaffected. CONCLUSIONS: A novel rare variant in CRYGD (Y134C) was detected in a Brazilian family with congenital cataract. Because there is no segregation between the substitution and the phenotypes in this family, other genetic alterations are likely to be present.

CYP1B1 gene analysis in primary congenital glaucoma Brazilian patients: novel mutations and association with poor prognosis.

PURPOSE: To determine the spectrum of CYP1B1 gene mutations in Brazilian patients with primary congenital glaucoma, and to correlate the presence of alterations in the CYP1B1 gene sequence with clinical aspects of the disease. MATERIALS AND METHODS: Thirty nonrelated patients with primary congenital glaucoma were studied. Molecular analysis consisted of the codifying region sequencing (exons 2 and 3) and intron/exon boundaries. RESULTS: CYP1B1 gene mutations were present in 9 (30%) of the 30 patients. The structural changes in the CYP1B1 gene previously described in the literature and observed in our study were Q19X, P437L, A443G, g.4340delG, g.7901_79013delGAGTGCAGGCAGA, g.8182delG, and g.8214_8215delG. Three new mutations were observed: 4635delT, 4523delC, and L378Q, in addition to 3793T→C, R48G, A119S, L432V, D449D, and N453S polymorphisms. Patients carrying CYP1B1 gene mutations needed more surgical procedures to control intraocular pressure, either when both eyes were evaluated (P=0.003) or when the worst eye of the patient was analyzed (P=0.011). In relation to the number of affected eyes, all patients with mutations (n=9/9) developed bilateral glaucoma, whereas 11/21 patients without mutations in the CYP1B1 gene had bilateral glaucoma (P=0.013). CONCLUSIONS: In this group of primary congenital glaucoma patients, a 30% mutation frequency in the CYP1B1 gene was observed. The presence of mutations was associated with a more severe form of the disease, requiring more surgeries for intraocular pressure control and with a higher rate of bilateral cases.

Lack of association between optineurin gene variants T34T, E50K, M98K, 691_692insAG and R545Q and primary open angle glaucoma in Brazilian patients.

PURPOSE: To verify the frequencies of T34T, E50K, M98K, 691_692insAG, and R545Q variants in the optineurin (OPTN) gene in Brazilian subjects with primary open-angle glaucoma (POAG) and controls. PATIENTS AND METHODS: Ninety-nine patients with POAG and 100 normal controls were enrolled in this study. The frequency of alterations in the OPTN gene was analyzed by direct sequencing and enzymatic digestion of PCR products. RESULTS: None of the five alterations evaluated was significantly associated with POAG when compared to controls. However, the T34T silent change was present in greater frequency in POAG patients (37.37% vs. 23.00% in controls), while the R545Q change was more prevalent in controls (23.00% vs. 10.10% in POAG). The M98K and 691_692insAG presented with low frequencies in POAG patients (1.01% and 2.02%, respectively) and controls (2.00% and 2.00%, respectively). The E50K substitution was not observed. CONCLUSION: Our data show no association between the five evaluated variants and POAG in the Brazilian population.

Evaluation of AC(n) and C(-106)T polymorphisms of the aldose reductase gene in Brazilian patients with DM1 and susceptibility to diabetic retinopathy.

PURPOSE: Diabetic retinopathy (DR) is one of the most important microvascular complications in both type 1 and type 2 diabetes. In Brazil, its proliferative form is the second cause of irreversible blindness among adults of working age. Despite the strong association of DR with disease duration and degree of chronic hyperglycemia, genetic predisposition has been recognized as a possible trigger in the development of this complication. Recent studies have demonstrated that the development of DR in patients with type 1 diabetes is associated with the occurrence of polymorphisms at the 5'-end of the aldose reductase gene (ALR2). There are no reports investigating these polymorphisms in type 1 diabetes Brazilian patients. The aim of this study was to investigate the relationship between the AC(n) repeat and C(-106)T polymorphisms of the ALR2 gene with the susceptibility to the development of DR in Brazilian patients with type 1 diabetes. METHODS: We selected 64 patients who had diabetes for at least 10 years from Santa Casa de São Paulo and State University of Campinas. The study group was divided into the following: Group 1, patients with no evidence of diabetic retinopathy; group 2, patients with nonproliferative diabetic retinopathy (NPDR); and group 3, patients with proliferative diabetic retinopathy (PDR), confirmed by fundoscopy. The AC(n) microsatellite region was evaluated through polymerase chain reaction (PCR) and automated genotyping and the C(-106)T substitution through polymerase chain reaction/restriction fragment length polymorphism (RFLP). RESULTS: When each allele of the AC(n) polymorphism was evaluated, the Z allele (24 repeats) was significantly associated with the development of PDR (p=0.014). The C allele of the C(-106)T substitution wasn't associated with the susceptibility to this microvascular complication (p=0.153). When the Z and C allele were concomitantly evaluated regarding their presence or absence a positive correlation was observed for the presence of both alleles and the development of PDR. CONCLUSIONS: In our sample of Brazilian patients with type 1 diabetes, the presence of the AC(n) polymorphism Z allele may be considered a risk factor for the development of PDR. The C allele of the C(-106)T polymorphism, in association with the Z allele, also increased the risk for the development of PDR, but when it was analyzed by itself there was no association with the complication.

Sensitivity and specificity of frequency-doubling technology, tendency-oriented perimetry, SITA Standard and SITA Fast perimetry in perimetrically inexperienced individuals.

PURPOSE: To evaluate the sensitivity and specificity of the screening modes of frequency-doubling technology (FDT), tendency-oriented perimetry (TOP), SITA Standard (SS) and SITA Fast (SF) in perimetrically inexperienced individuals. METHODS: One eye of 64 glaucoma patients and 53 normal subjects who had never undergone automated perimetry were tested with programs C-20-5 (FDT), G1 (TOP) and 24-2 (SS and SF). The gold standard for glaucoma was the presence of a typical glaucomatous optic disc appearance on stereoscopic examination (judged by a glaucoma expert), and intraocular pressure (IOP) > 21 mmHg. The test order among strategies was randomized for each subject. To define an abnormal visual field, we applied three criteria for SS and SF and two criteria for TOP and FDT, all of which have been previously described in the literature. Sensitivities and specificities among the different criteria were compared using the Cochran test. RESULTS: Frequency-doubling technology showed the shortest mean test duration, followed by TOP, SF and SS (p < 0.05). Sensitivity ranges were 87.5-89.1% for SS, 92.2-93.8% for SF, 87.5-89.1% for TOP, and 82.8-85.9% for FDT (p = 0.34). Specificity ranges were 73.6-83% for FDT, 56.6-62.3% for TOP, 60.4-69.8% for SF and 66.0-71.7% for SS. The specificity obtained with criterion 2 for FDT (based on the presence of two or more abnormal locations regardless of the severity of abnormal points) was higher than those measured with the other strategies (p < 0.01). CONCLUSION: When testing individuals with no perimetric experience, moderate sensitivities and specificities should be expected, regardless of the strategy chosen.