Pedigree of the family illustrating the segregation of four disease-causing ABCA4 alleles with two Stargardt disease (STGD1) phenotypes of varying severity. Filled circles and squares denote affected males and females, respectively, and centrally filled shapes denote heterozygous carriers. ABCA4 variants, and their order on the chromosome, are listed in the key. The symbol (+) denotes the presence of a disease-causing ABCA4 variant while (−) represents the wild-type allele. The mother of the proband (I-2, arrowhead) was affected with pattern macular dystrophy which was phenotypically distinct from the other affected individuals and the father (I-1) was affected with chronic central serous chorioretinopathy.