In conclusion, this study investigated 4 unrelated families with autosomal recessive LCA/EORD associated with biallelic pathogenic variants in the SLC6A6 gene, extending observations on single pedigrees from previous reports15,16,17 and confirming the association between SLC6A6/TauT and retinal disease. This evidence concerns the gene SLC6A6 and Leber congenital amaurosis.