Comparative transcriptomic analysis of circulating endothelial cells in sickle cell stroke.

Ischemic stroke (IS) is one of the most impairing complications of sickle cell anemia (SCA), responsible for 20% of mortality in patients. Rheological alterations, adhesive properties of sickle reticulocytes, leukocyte adhesion, inflammation and endothelial dysfunction are related to the vasculopathy observed prior to ischemic events. The role of the vascular endothelium in this complex cascade of mechanisms is emphasized, as well as in the process of ischemia-induced repair and neovascularization. The aim of the present study was to perform a comparative transcriptomic analysis of endothelial colony-forming cells (ECFCs) from SCA patients with and without IS. Next, to gain further insights of the biological relevance of differentially expressed genes (DEGs), functional enrichment analysis, protein-protein interaction network (PPI) construction and in silico prediction of regulatory factors were performed. Among the 2469 DEGs, genes related to cell proliferation (AKT1, E2F1, CDCA5, EGFL7), migration (AKT1, HRAS), angiogenesis (AKT1, EGFL7) and defense response pathways (HRAS, IRF3, TGFB1), important endothelial cell molecular mechanisms in post ischemia repair were identified. Despite the severity of IS in SCA, widely accepted molecular targets are still lacking, especially related to stroke outcome. The comparative analysis of the gene expression profile of ECFCs from IS patients versus controls seems to indicate that there is a persistent angiogenic process even after a long time this complication has occurred. Thus, this is an original study which may lead to new insights into the molecular basis of SCA stroke and contribute to a better understanding of the role of endothelial cells in stroke recovery.

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.

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.

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.

Transcriptomics and network analysis highlight potential pathways in the pathogenesis of pterygium.

Pterygium is a common ocular surface condition frequently associated with irritative symptoms. The precise identity of its critical triggers as well as the hierarchical relationship between all the elements involved in the pathogenesis of this disease are not yet elucidated. Meta-analysis of gene expression studies represents a novel strategy capable of identifying key pathogenic mediators and therapeutic targets in complex diseases. Samples from nine patients were collected during surgery after photo documentation and clinical characterization of pterygia. Gene expression experiments were performed using Human Clariom D Assay gene chip. Differential gene expression analysis between active and atrophic pterygia was performed using limma package after adjusting variables by age. In addition, a meta-analysis was performed including recent gene expression studies available at the Gene Expression Omnibus public repository. Two databases including samples from adults with pterygium and controls fulfilled our inclusion criteria. Meta-analysis was performed using the Rank Production algorithm of the RankProd package. Gene set analysis was performed using ClueGO and the transcription factor regulatory network prediction was performed using appropriate bioinformatics tools. Finally, miRNA-mRNA regulatory network was reconstructed using up-regulated genes identified in the gene set analysis from the meta-analysis and their interacting miRNAs from the Brazilian cohort expression data. The meta-analysis identified 154 up-regulated and 58 down-regulated genes. A gene set analysis with the top up-regulated genes evidenced an overrepresentation of pathways associated with remodeling of extracellular matrix. Other pathways represented in the network included formation of cornified envelopes and unsaturated fatty acid metabolic processes. The miRNA-mRNA target prediction network, also reconstructed based on the set of up-regulated genes presented in the gene ontology and biological pathways network, showed that 17 target genes were negatively correlated with their interacting miRNAs from the Brazilian cohort expression data. Once again, the main identified cluster involved extracellular matrix remodeling mechanisms, while the second cluster involved formation of cornified envelope, establishment of skin barrier and unsaturated fatty acid metabolic process. Differential expression comparing active pterygium with atrophic pterygium using data generated from the Brazilian cohort identified differentially expressed genes between the two forms of presentation of this condition. Our results reveal differentially expressed genes not only in pterygium, but also in active pterygium when compared to the atrophic ones. New insights in relation to pterygium's pathophysiology are suggested.

Epigenetic analysis in placentas from sickle cell disease patients reveals a hypermethylation profile.

Pregnancy in Sickle Cell Disease (SCD) women is associated to increased risk of clinical and obstetrical complications. Placentas from SCD pregnancies can present increased abnormal findings, which may lead to placental insufficiency, favoring adverse perinatal outcome. These placental abnormalities are well known and reported, however little is known about the molecular mechanisms, such as epigenetics. Thus, our aim was to evaluate the DNA methylation profile in placentas from women with SCD (HbSS and HbSC genotypes), compared to uncomplicated controls (HbAA). We included in this study 11 pregnant women with HbSS, 11 with HbSC and 21 with HbAA genotypes. Illumina Methylation EPIC BeadChip was used to assess the whole placental DNA methylation. Pyrosequencing was used for array data validation and qRT-PCR was applied for gene expression analysis. Our results showed high frequency of hypermethylated CpGs sites in HbSS and HbSC groups with 73.5% and 76.2% respectively, when compared with the control group. Differentially methylated regions (DMRs) also showed an increased hypermethylation status for the HbSS (89%) and HbSC (86%) groups, when compared with the control group methylation data. DMRs were selected for methylation validation (4 DMRs-HbSS and 3 DMRs the HbSC groups) and after analyses three were validated in the HbSS group, and none in the HbSC group. The gene expression analysis showed differential expression for the PTGFR (-2.97-fold) and GPR56 (3.0-fold) genes in the HbSS group, and for the SPOCK1 (-2.40-fold) and ADCY4 (1.80-fold) genes in the HbSC group. Taken together, these data strongly suggest that SCD (HbSS and HbSC genotypes) can alter placental DNA methylation and lead to gene expression changes. These changes possibly contribute to abnormal placental development and could impact in the clinical course, especially for the fetus, possibly leading to increased risk of abortion, fetal growth restriction (FGR), stillbirth, small for gestational age newborns and prematurity.

Demographic history differences between Hispanics and Brazilians imprint haplotype features.

Admixture is known to greatly impact the genetic landscape of a population and, while genetic variation underlying human phenotypes has been shown to differ among populations, studies on admixed subjects are still scarce. Latin American populations are the result of complex demographic history, such as 2 or 3-way admixing events, bottlenecks and/or expansions, and adaptive events unique to the American continent. To explore the impact of these events on the genetic structure of Latino populations, we evaluated the following haplotype features: linkage disequilibrium, shared identity by descent segments, runs of homozygosity, and extended haplotype homozygosity (integrated haplotype score) in Latinos represented in the 1000 Genome Project along with array data from 171 Brazilians sampled in the South and Southeast regions of Brazil. We found that linkage disequilibrium decay relates to the amount of American and African ancestry. The extent of identity by descent sharing positively correlates with historical effective population sizes, which we found to be steady or growing, except for Puerto Ricans and Colombians. Long runs of homozygosity, a particular instance of autozygosity, was only enriched in Peruvians and Native Americans. We used simulations to account for random sampling and linkage disequilibrium to filter positive selection indexes and found 244 unique markers under selection, 26 of which are common to 2 or more populations. Some markers exhibiting positive selection signals had estimated time to the most recent common ancestor consistent with human adaptation to the American continent. In conclusion, Latino populations present highly divergent haplotype characteristics that impact genetic architecture and underlie complex phenotypes.

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.

"Association of APOE gene polymorphisms with primary open angle glaucoma in Brazilian patients".

Background: Primary open-angle glaucoma (POAG) is a multifactorial disease that affects 65.5 million people worldwide. In addition to the genetic variants already established as indicators of greater risk for POAG, the apolipoprotein (APOE) gene has been studied in some populations, with controversial results. The aim of this study is to investigate the frequency of the genetic variants of APOE in the Brazilian population, and to evaluate the association between these polymorphisms and the risk of POAG. Methods: APOE variants (rs429358; rs7412) were genotyped in 402 POAG patients and 401 controls. We evaluated the association between APOE genetic variants and the risk for POAG, as well as the correlation between the requirement of glaucoma surgery and the APOE polymorphisms. Results: Among the three APOE gene isoforms, we found a low frequency of APOE alleles ε2 (7.34%) and ε4 (11.76%), but a high frequency of ε3 (80.88%) in our population. When compared to ε3ε3 reference genotype, ε2 allele-carriers (OR = 1.516; p-value = 0.04) and ε2ε3 genotype (OR = 1.655; p-value = 0.02) were associated with a greater risk for POAG. An additive genetic model confirmed the influence of the ε2 allele in the risk of POAG in this sample of the Brazilian population (OR = 1.502; p-value = 0.04). There was no significant association between the analyzed genotypes and the requirement or number of glaucoma surgeries (p > .05). Conclusion: Brazilian individuals carrying the APOEε2 allele may be at an increased risk for the development of POAG.

Interleukin-1ß-31 (rs1143627) genetic variant and the risk of age-related macular degeneration in the Brazilian population.

Background: Age-related macular degeneration (AMD) is a multifactorial disease and one of the main causes of blindness in people over 50 years old. The etiology and pathophysiology of AMD are not well understood. The aim of this study was to investigate whether the rs1143627 variant allele of IL1B, which encodes Interleukin (IL)-1ß, a key cytokine, mediates immune and inflammatory responses.Methods: A case-control study was conducted with 397 AMD patients and 402 controls in Brazil. IL1B genotyping was carried out with TaqMan® genotyping assay. Differences in IL1B allele frequencies and genotypes were evaluated between patients and controls and between wet and dry subgroups of AMD. Relationships between allele presence/genotype and disease risk are reported as odds ratios (ORs) with 95% confidence intervals (CIs).Results: Genotype proportions for the rs1143627 variant allele of IL1B were similar between AMD patients and controls (p = .21), with 84.38% of AMD patients and 79.60% of the controls carrying the variant allele. We observed a trend toward the variant allele being associated with AMD risk (OR = 1.38, 95% CI 0.95-2.03, p = .08), as well as a trend toward the variant allele being associated with increased risk for wet AMD in particular (OR = 1.23, 95% CI 0.96-1.56, p = .08).Conclusions: The rs1443627 variant was not associated with AMD risk in this Brazilian population sample. Larger studies are warranted to determine whether the trends observed in this study reflect a relationship between this variant and risk of AMD, especially wet AMD.

High levels of human gamma-globin are expressed in adult mice carrying a transgene of the Brazilian type of hereditary persistence of fetal hemoglobin ((A)gamma -195).

Hereditary persistence of fetal hemoglobin (HPFH) is characterized by increased levels of Hb F during adult life. Nondeletional forms of HPFH are characterized by single base mutations in the (A)gamma and (G)gamma promoters, resulting in an increase of Hb F ranging from 3 to 20% in heterozygotes. Many point mutations in this region have been described, including the (A)gamma -195 (C>G) mutation that causes the Brazilian type of HPFH (HPFH-B). To better understand this mechanism, we have developed HPFH-B transgenic mice. mRNA levels of human gamma-globin of -195 transgenic mice were clearly higher when compared with control transgenic mice bearing a wild type sequence of the gamma promoter. Thus, our data indicate that the -195 mutation is the unique cause of elevation of Hb F in Brazilian HPFH. These results could provide us with an opportunity to study the modifying effects of the Hb F in the phenotype of sickle cell disease and beta-thalassemia (beta-thal).

Genetic comparison of sickle cell anaemia cohorts from Brazil and the United States reveals high levels of divergence.

Genetic analysis of admixed populations raises special concerns with regard to study design and data processing, particularly to avoid population stratification biases. The point mutation responsible for sickle cell anaemia codes for a variant hemoglobin, sickle hemoglobin or HbS, whose presence drives the pathophysiology of disease. Here we propose to explore ancestry and population structure in a genome-wide study with particular emphasis on chromosome 11 in two SCA admixed cohorts obtained from urban populations of Brazil (Pernambuco and São Paulo) and the United States (Pennsylvania). Ancestry inference showed different proportions of European, African and American backgrounds in the composition of our samples. Brazilians were more admixed, had a lower African background (43% vs. 78% on the genomic level and 44% vs. 76% on chromosome 11) and presented a signature of positive selection and Iberian introgression in the HbS region, driving a high differentiation of this locus between the two cohorts. The genetic structures of the SCA cohorts from Brazil and US differ considerably on the genome-wide, chromosome 11 and HbS mutation locus levels.

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.

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.

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.

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.

Structural assessment of PITX2, FOXC1, CYP1B1, and GJA1 genes in patients with Axenfeld-Rieger syndrome with developmental glaucoma.

PURPOSE: Axenfeld-Rieger (AR) is an autosomal dominant disorder with phenotypic heterogeneity characterized by anterior segment dysgenesis, facial bone defects, and redundant periumbilical skin. The PITX2 gene, on chromosome 4q25, and the FOXC1 gene, on chromosome 6p25, have been implicated in the different phenotypes of the syndrome through mutational events. Recently, the CYP1B1 gene was found to be associated with Peters' anomaly, and the gene associated with oculodentodigital dysplasia syndrome, which presents some similarities with AR, was identified (connexin 43--GJA1 gene). The purpose of this study was to evaluate PITX2, FOXC1, CYP1B1, and GJA1 gene mutations in Brazilian families with AR. METHODS: Eight unrelated patients affected by AR (all eight with glaucoma and three with systemic manifestations) and their families were ophthalmologically evaluated and their blood was collected for DNA extraction purposes. The coding regions of PITX2, FOXC1, CYP1B1, and GJA1 genes were completely evaluated through direct sequencing. RESULTS: The frequency of mutations in the FOXC1, GJA1, PITX2, and CYP1B1 genes in this study were 25%, 12.5%, 0% and 0%, respectively. In the FOXC1 gene, two GGC triplet insertions (GGC375ins and GGC447ins) defined as a polymorphism, and two new mutations--a deletion (718 to 719delCT) and a nonsense mutation (Trp152STOP)--were identified. One polymorphism (Ala253Val) was identified in the GJA1 gene in the same family presenting the Trp152STOP mutation in the FOXC1 gene. In this family harboring both structural alterations, two patients who carried the GJA1 (Ala253Val) and FOXC1 (Trp152STOP) mutations developed less severe glaucoma compared with family members presenting the FOXC1 (Trp152STOP) mutation alone. CONCLUSIONS: Two new structural alterations in the FOXC1 gene and a polymorphism in the GJA1 gene were first described in Brazilian patients with AR and developmental glaucoma. A polymorphism in the GJA1 gene (Ala253Val), for the first time identified in association with AR, raises the possibility of its participation as a modifier gene.

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.