MITOCHONDRIAL DYSFUNCTION IN LEIGH SYNDROME: FROM GENETIC BASIS TO THERAPEUTIC APPROACHES

Leigh syndrome (LS), also known as subacute necrotizing encephalomyelopathy, is a rare, genetically determined metabolic disorder caused by primary or secondary dysfunction of the mitochondrial electron transport chain. It typically manifests in early childhood, before the age of two, primarily affecting the nervous system and often resulting in premature death. Mouse models with silenced NDUFS4 genes demonstrate symptoms similar to human LS, including ataxia, growth retardation, respiratory dysfunction, and elevated lactate levels in the blood and cerebrospinal fluid, with mortality rates reaching 90%. LS inheritance patterns include autosomal recessive, mitochondrial, or X-linked recessive mechanisms. Most cases involve mutations in nuclear DNA, with fewer linked to mitochondrial DNA (mtDNA). Over 75 causative genes have been identified, with MT-ATP6 mutations being the most common, responsible for maternally inherited Leigh syndrome (MILS). Diagnostic approaches include prenatal testing, brain imaging (e.g., magnetic resonance imaging), and biochemical tests measuring lactate in blood and cerebrospinal fluid. There is currently no effective treatment; available therapies focus on vitamin supplementation and symptom management to improve patients’ quality of life. This study aims to review current knowledge on Leigh syndrome, including its etiology, clinical presentation, diagnostic methods, and available therapies. Emphasis is placed on the disorder’s genetic basis and the diversity of mutations involved, providing insights into the underlying mechanisms and potential research directions.