Association between the ARMS2 rs10490924 risk genotype and dry-age related macular degeneration patients with and without reticular pseudodrusen in a Turkish population: findings from a study conducted at a tertiary clinic.

Purpose: To evaluate the relationship between the presence of reticular pseudodrusen (RPD) and the risk allele of ARMS2 rs10490924 variation in dry-AMD patients by using multimodal imaging. Also, to compare patients with and without RPD and healthy volunteers according to the distribution of the risk allele.

Methods: In this cross-sectional study, dry-AMD patients with (Group A, n = 50) and without (Group B, n = 50) RPD and healthy volunteers (Group C, n = 50) were enrolled. After detailed ophthalmologic examination, confocal scanning laser ophthalmoscope (Heidelberg, Germany) was used to acquire near infra-red (NIR) imaging for RPD and the diagnosis was confirmed by Spectral Domain-Optical coherence tomography (Heidelberg, Germany). In silent choroidal neovascularization suspicion, optical coherence tomography angiography (Optovue, Fremont, CA) was performed and those were excluded. For genetic assessment, peripheric blood sampling was performed. Using next-generation sequencing technique (NGS), ARMS2 rs10490924 single nucleotide polymorphism was investigated. Groups were compared according to the distribution of the risky allele.

Results: 150 eyes of 150 participants were included. In Group A, 42% (21) of patients were heterozygous for the T risk allele, 30% (15) were homozygous, and the risk allele was not detected in 28% (14). In Group B, 44% (22) of patients were heterozygous, 17% (8) were homozygous, and the risk allele was not detected in 39% (20). In Group C, 30% (15) of participants were heterozygous, 4% (2) were homozygous, and variation was not observed in 64% (32). Homozygous participants in Group A were significantly higher than other two groups (Group A-B: OR = 2.67, 95% CI: 0.895, 8.020; Group A-C: OR = 17.14, 95% CI: 3.449, 85.208) while in Group B, homozygous individuals were higher than Group C (respectively, p values 0.0039, 0.0002, 0.013). T risky allele frequencies were 51%, 38%, and 20% in Groups A, B, and C, respectively, which was significantly higher in Group A (p = 0.02).

Conclusion: Genetic influence in AMD is inevitable while certain differences according to different ethnicities may apply. Association of genetic variations and imaging findings like RPD is lacking among literature for different populations. By the aspect of this study, the relationship between RPD and ARMS2 rs10490924 polymorphism in dry-AMD patients were highlighted among Turkish population by using multimodal imaging for the first time.

Key messages: What is Known? Pathophysiology of age-related macular degeneration is influenced from multiple factors including single nucleotide polymorphisms. The variations of ARMS2 are suspected well in the current literature. Reticular pseudodrusen is related to advanced stages of age related macular degeneration disease. What is New? The ARMS2 rs10490924 risk genotype is associated with the presence of reticular pseudodrusen in dry age related macular degeneration patients. Homozygous genotype of T risk allele is evaluated significantly higher in dry age related macular degeneration patients with reticular pseudodrusen.