Various phenotypic features have been reported in OMD caused by monoallelic RP1L1 variants (RP1L1-OMD; Miyake disease) and other disorders with macular dysfunction and normal fundus (non-RP1L1 OMD), and the disease spectrum of occult macular dysfunction syndrome (OMDS), including hereditary and possibly non-hereditary diseases, was first suggested in 2016 [11]. The gene discussed is RP1L1; the disease is hereditary disease.