Genetics of Age-Related Macular Degeneration ?
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Age-related macular degeneration (AMD) is a common polygenic disease in which multiple genetic variants, as well as environmental and lifestyle factors, contribute to disease risk, each adding a small to moderate amount of increased risk. The risk of developing the disease is at least three-fold higher in people who have a family member with AMD than in those without a first-degree relative with AMD. This risk is amplified when immediate family members have the disease, with one study estimating a 27.8 times increased risk with an affected parent and 12 times increased risk for those with an affected sibling
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@anupam Several genetic variants have been consistently associated with AMD. The common coding variant Y402H in the complement factor H (CFH) gene was the first identified. The odds ratio associated with being homozygous for the risk variant for all categories of AMD is estimated to be between 2.45 and 3.33; the odds ratios are higher, between 3.5 and 7.4, for advanced dry and wet forms of AMD. Several other genetic loci in the alternative complement cascade have also been consistently shown to affect AMD risk. These include other variants in CFH, as well as other genes: factor B (BF)/complement component 2 (C2), complement component 3 (C3), and complement factor I (CFI). Several genes not involved in the complement cascade have also been implicated. Variation in the HTRA1/ARMS2 locus on chromosome 10 has been convincingly associated with AMD, with an effect size similar to or greater than that seen with CFH. The function of this gene is not completely understood, but there is evidence that it confers greater risk for wet AMD than for geographic atrophy.