Purpose. Åland Island eye disease (AIED), also known as Forsius-Eriksson syndrome, is an X-linked recessive retinal disease characterized by a combination of fundus hypopigmentation, decreased visual acuity, nystagmus, astigmatism, protan color vision defect, progressive myopia, and defective dark adaptation. Electroretinography reveals abnormalities in both photopic and scotopic functions. The gene locus for AIED has been mapped to the pericentromeric region of the X-chromosome, but the causative gene is unknown. The purpose of this study was to identify the mutated gene underlying the disease phenotype in the original AIED-affected family.