Mitochondrion. 2012 Nov;12(6):617-22. doi: 10.1016/j.mito.2012.10.002. Epub 2012 Oct 10.
Heteroplasmic m.1624C>T mutation of the mitochondrial tRNA(Val) gene in a proband and his mother with repeated consciousness disturbances.
Homoplasmic m.1624C>T mutation of the mitochondrial tRNA(Val) gene was previously demonstrated to cause fatal neonatal Leigh syndrome. Here, we report the clinical phenotypes of a Japanese male and his mother with heteroplasmic m.1624C>T mutation. The 36-year-old male presented with repeated episodes of consciousness disturbance since the age of 25, cognitive decline, and personality change. Cerebrospinal fluid levels of lactate and pyruvate were elevated. His mother showed similar symptoms and course. The mutation m.1624C>T was identified heteroplasmically in the proband's muscle and leukocytes and in the mother's leukocytes. The heteroplasmy load decreased with age.