De Novo Mutation in the Mitochondrial tRNA Leu(UUR) Gene (A3243G) with Rapid Segregation Resulting in MELAS in the Offspring
February 2001
in “
Journal of paediatrics and child health
”
TLDR A new mutation in the mitochondrial DNA was found in a boy with MELAS, even though his family didn't show typical signs.
A 14-year-old Chinese boy presented with multisystem involvement, including migraine, epilepsy, ataxia, and mental deterioration, starting at age 5. Imaging revealed multiple cerebral infarcts, and elevated lactate levels were noted. Mitochondrial DNA analysis identified a heteroplasmic A3243G mutation in the tRNA^Leu(UUR) gene across various tissues. The boy's asymptomatic mother and brother also carried the mutation, while other maternal relatives did not, indicating a de novo mutation. This case highlighted that the absence of ragged red fibers in muscle biopsy did not rule out mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), and genetic testing confirmed the diagnosis.
