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.

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.

"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.