Phosphorus MR spectroscopy shows a tissue specific in vivo distribution of biochemical expression of the G3460A mutation in Leber's hereditary optic neuropathy. Issue 6 (1st June 2002) - Lodi, R
Abstract : Occipital lobe and calf muscle energy metabolism were studied in vivo by magnetic resonance spectroscopy ( 31 P-MRS) in four members of a family harbouring the mitochondrial DNA G3460A mutation causing Leber's hereditary optic neuropathy (LHON). Three siblings carried 100% mutated mitochondrial DNA (homoplasmy), while their mother had coexistence of mutated and wild-type mitochondrial DNA (heteroplasmy). Indices of brain energy metabolism on 31 P-MRS were abnormal in all subjects examined, but the muscle oxidative phosphorylation rate was normal. These findings indicate a tissue specific distribution of the biochemical expression of the G3460A LHON mutation and suggest that extramitochondrial factors, such as nuclear genes, may influence expression of this mutation in vivo.