Association of Single Nucleotide Polymorphisms in CFH, ARMS2 and HTRA1 Genes with Risk of Age-related Macular Degeneration in Egyptian Patients

ABSTRACT

Background: Age-related macular degeneration (AMD) is one of the leading causes of blindness in the elderly worldwide. Several single nucleotide polymorphisms (SNPs) have been linked to the risk of developing AMD. We aimed to examine the association between AMD and SNPs on CFH, ARMS2 and HTRA1 in Egyptians, a previously unstudied population.

Materials and methods: Genomic DNA was extracted from 26 AMD patients and 20 controls. Genotyping was performed using PCR followed by allele-specific restriction digestion and direct sequencing.

Results: CFH rs1061170 was significantly associated with AMD with the frequency of the risk C allele being 0.53 in patients and 0.17 in controls (p < 0.017). The odds ratio (OR) for the TC genotype was 5.5 (95% CI: 1.1–26.4) and for combined TC + CC genotypes was 8 (95% CI: 1.7–37.1). ARMS2 rs10490924 was also significantly associated with the risk allele T found at a frequency of 0.5 in AMD and 0.15 in controls (p < 0.017, χ² test). The OR for the TG genotype was 4.667 (95% CI: 1.2–18.4) and for combined TG + TT genotypes was 7 (95% CI: 1.8–26.5). HTRA1 rs11200638 also was significantly associated, with the risk allele A found at a frequency of 0.44 in patients and 0.17 in controls (p < 0.017, χ² test). OR for GA genotype was 5 (95% CI: 1.2–20.9) and for the combined GA + AA genotypes was 6 (95% CI: 1.4–24.7).

Conclusions: Our data demonstrates significant association between AMD and rs1061170 on CFH, rs10490924 on ARMS2 and rs11200638 on HTRA1 in Egyptian patients. These findings are in agreement with previous findings in Caucasians.

• Age-related macular degeneration
• ARMS2
• CFH
• Egypt
• HTRA1

ACKNOWLEDGEMENTS

The authors would like to acknowledge Dr Maged Mikhael at the National Eye Research Center in Road el Farag, Dr Tharwat Mokbel at Mansoura University Medical School and Dr Sherif Karawya at The Research Institute of Ophthalmology in Giza for the great help they provided us during the sample collection stage of this research. He authors also thank Dr W. Edward Highsmith at Mayo Clinic, Rochester, MN for his useful comments and feedback.