LEBERS HEREDITARY OPTIC NEUROPATHY - HETEROPLASMY IS LIKELY TO BE SIGNIFICANT IN THE EXPRESSION OF LHON IN FAMILIES WITH THE 3460-ND1 MUTATION

Aim-To assess the effect of heteroplasmy on the expression of Leber's hereditary optic neuropathy (LHON) in a large family with the 3460 LHO N mutation. Methods-A Mutation detection was performed by restriction enzyme digestion of polymerase chain reaction (PCR) products. Heteropl asmy was estimated by quantitation of wild type:mutant product ratios. Results-There is a significant association between levels of mutant m tDNA and manifestation of the disease phenotype. Conclusion-As a high proportion of families with the 3460 mutation demonstrate heteroplasmy ; this is likely to be a significant factor in disease expression.