Complement Component C3 Variant (R102G) and the Risk of Neovascular Age-Related Macular Degeneration in a Tunisian Population

Abstract

Purpose To explore the association between the polymorphism (S/F) p.R102G in the complement component 3 (C3) gene and age-related macular degeneration (AMD) in a Tunisian population.

Methods The molecular study was performed by polymerase chain reaction using sequence-specific primers (PCR-SSP) in 207 control subjects free of any eye disease (fundus normal) and 145 patients with exudative AMD. The CH50 activity and quantification of C3 and C4 have been made by technical home method and nephelometry, respectively.

Results The prevalence of C3 GG genotype polymorphism was significantly higher in AMD patients compared to controls (OR: 2.41, IC 95% [1.90–3.05], p = 0.0007). However, no correlation was found between this allelic variant and the type of neovascularization. Similarly, there is no association between this polymorphism and the presence of functional and/or quantitative hypocomplementemia.

Conclusions The C3 GG genotype of the gene could be a susceptibility factor for AMD in the Tunisian population. However, it does not seem to influence the clinical profile of the disease.

Zusammenfassung

Absicht Die Verbindung zwischen dem Polymorphismus (S/F) p.R102G des Komplementbestandteils im C3-Gen und der altersbedingten Makuladegeneration (AMD) in der tunesischen Bevölkerung erforschen.

Methode Die molekulare Studie wurde durch PCR-SSP an 207 gesunden Kontrollpersonen (normaler Fundus) und 145 Patienten mit exsudativer AMD durchgeführt. Die CH50-Aktivität und die Quantifizierung des C3- und C4-Komplements wurden durch hauseigene technische Verfahren sowie mit Nephelometrie gemessen.

Resultate Die Prävalenz des C3-Genotyp-Polymorphismus war erheblich höher bei AMD-Patienten gegenüber gesunden Kontrollprobanden (OR: 2.41, IC 95% [1.90–3.05], p = 0.0007). Allerdings wurde kein Zusammenhang zwischen dieser Allelenvariante und verschiedenen Typen von Neovaskularisationen festgestellt. Ebenso gab es keinen Zusammenhang zwischen diesem Polymorphismus und der Prävalenz einer funktionalen und/oder quantitativen Hypokomplementämie.

Ergebnis Der C3-GG-Genotyp des Gens könnte ein Screeningmerkmal für AMD in der tunesischen Bevölkerung sein. Allerdings scheint es nicht das klinische Profil der Erkrankung zu beeinflussen.

Key words

AMD - C3 - complement

Schlüsselwörter

AMD - C3 - Komplement

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