ABSTRACT

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.

摘要

背景：原发性开角型青光眼 (POAG) 是一种多因素疾病，影响全球 6550 万人。除了已经确定为 POAG 更大风险指标的遗传变异外，载脂蛋白 ( APOE ) 基因已在一些人群中进行了研究，但结果有争议。本研究的目的是调查巴西人群中APOE遗传变异的频率，并评估这些多态性与 POAG 风险之间的关联。

方法：在 402 名 POAG 患者和 401 名对照中对APOE变体（rs429358；rs7412）进行基因分型。我们评估了APOE遗传变异与 POAG 风险之间的关联，以及青光眼手术要求与APOE多态性之间的相关性。

结果：在三个APOE基因亚型中，我们发现APOE等位基因ε2（7.34%）和ε4（11.76%）频率较低，而ε3（80.88%）频率较高。与 ε3ε3 参考基因型相比，ε2 等位基因携带者（OR = 1.516；p值 = 0.04）和 ε2ε3 基因型（OR = 1.655；p值 = 0.02）与更大的 POAG 风险相关。加性遗传模型证实了 ε2 等位基因对巴西人口样本中 POAG 风险的影响（OR = 1.502；p值 = 0.04）。分析的基因型与青光眼手术的要求或数量之间没有显着关联（p > .05）。

结论：携带APOE ε2 等位基因的巴西人患 POAG 的风险可能增加。