The Italian reappraisal of the most frequent genetic defects in hereditary optic neuropathies and the global top 10

We read with great interest the recent publication by Rocatcher and colleagues1 entitled ‘The top 10 most frequently involved genes in hereditary optic neuropathies in 2186 probands’, reporting on the experience of a national diagnostic centre for hereditary optic neuropathies (HON) in France. Similarly, our scientific institute is a national referral and diagnostic centre for HON in Italy, and in this correspondence, we present our neurogenetic assessments of 1097 HON patients. We offer a comparison between the two studies and comment on the global results obtained by merging the data, thus commenting on the largest cohort of HON cases presented to date.