Based on the review of Scholl et al [21] and the large twin study of Seddon et al [22] we have used a prevalence after 80 years age of advanced AMD K = 11.8% and a sibling recurrence risk representing the genetic contribution of λS = 2.2, which correspond to heritability on the liability scale of = 0.68 (equation 1). If the genetic test explains all the genetic variance ( = 1), the maximum AUC that could be achieved by a genomic profile is AUCmax = 0.92. If only half or a quarter of the genetic variance can be detected by genomic markers then the maximum AUC that can achieved are AUChalf = 0.81 and AUCquar = 0.72, respectively, values that exceed the prediction of genetic risk based of the most optimistic scenario from a prediction based on family history (Text S1). If complete disease status is known for all siblings, parents, grandparents, aunts, uncles and cousins then the maximum AUC that could be achieved is 0.71, translating to a genomic profile that explains 0.21 of the genetic variance (Table
