However, optic atrophy was evident in all the other OPA1-mutant subjects, being often the first and main symptom; in contrast, in our patients overt optic atrophy was observed later compared to most of the other neurological signs (P1 and P3) or not reported (P1’s brother and P3, untill 10 years of age). This evidence concerns the gene OPA1 and hereditary optic atrophy.