The ε4 allele of the apolipoprotein E gene as a potential protective factor for exudative age-related macular degeneration

PURPOSE: Apolipoprotein E (ApoE) is a polymorphic protein that plays a central part in plasma metabolism of lipids and in central nervous system lipid homeostasis. Our purpose was to evaluate the potential role of ApoE polymorphism in the occurrence of exudative age-related macular degeneration associated with drusen, which contain lipids. METHODS: We analyzed apolipoprotein E genotypes in 116 unrelated patients with exudative age-related macular degeneration in one eye and hard drusen (n = 39) or soft drusen (n = 77) in the other eye, and compared the results with those of age matched and sex matched control subjects (n = 168). Apolipoprotein E alleles were detected by a polymerase chain reaction-based method. RESULTS: A lower frequency of the epsilon 4 allele carriers was observed in the exudative age-related macular degeneration group compared with control subjects (12.1% vs 28.6%, respectively; P < .0009). The epsilon 4 allele was less frequent in the age-related macular degeneration group compared with control subjects (0.073 vs 0.149, respectively; P < .006). This decreased frequency of the epsilon 4 allele was mainly observed in the soft drusen subgroup compared with control subjects (0.045 vs 0.149, respectively; P < .0009). CONCLUSION: This lower relative frequency of the epsilon 4 allele supports the hypothesis that the ApoE gene is a genetic protective factor identified in age related macular degeneration. (C) 1998 by Elsevier Science Inc. All rights reserved.