Highly efficient mtDNA editing in C57BL/6J mouse embryos was demonstrated using DdCBE to induce two possible silent mutations: m.12918G > A (ortholog of human m.13513G > A), associated with multiple mitochondrial diseases such as Leigh disease, MELAS syndrome, LHON and LHON/MELAS overlap syndrome in humans, and m.12336C > T, which incorporates a premature stop codon in the MT-ND5 gene [2,146,150]. This evidence concerns the gene MT-ND5 and Leigh syndrome.