Three subgroups of patients from the United Kingdom with Leber hereditary optic neuropathy.

Variations in classic Leber hereditary optic neuropathy (LHON) include recovery of vision and association with other neurological abnormalities. Sixteen multi-generational Australian families originating from the United Kingdom with LHON were studied by the one examiner, using the same protocol. In particular, recovery of vision and other neurological abnormalities were noted. One very large family (Tas2) and one small family (Vic2) were found to have frequent recovery of vision (50% of patients). They both had the 14484 T to C mutation in their mitochondrial DNA (mtDNA). One apparently unique family (Qld1) was found to have frequent juvenile encephalopathy and peripheral neurological signs. They had the 4160 T to C and 14484 T to C mutations. The remaining 13 families rarely showed visual recovery or associated neurological abnormalities. They had the common 11778 G to A or the 3460 G to A mutations. Thus mitochondrial genotypes in LHON are associated with variable phenotypes.