,5 Following initial publications defining this locus6,7 a variant in CA4 was implicated as the cause of adRP in families of South African origin, however pathogenicity of the reported variant has been questioned because it has a population frequency of 4% in healthy controls in northern Sweden.8, 9, 10 Subsequently reported CA4 variants in individuals with RP were identified by targeted Sanger sequencing and do not fully exclude variants in other genes as a cause of disease (Table S1). This evidence concerns the gene CA4 and retinitis pigmentosa 1.