In our cohort, dual genetic diagnosis was obtained by the combination of genomic rearrangement and a monogenic disease produced by a non-syndromic IRD gene (RP-1018 and RP-1321); this finding is in line with a previously reported case by our group of a proband solved with biallelic variants in USH2A (USH) and a de novo microdeletion at 17q21.31 (Koolen-de Vries syndrome, MIM #610443) (Sanchez-Navarro et al. 2018). The gene discussed is USH2A; the disease is Koolen-de Vries syndrome.