GNAO1 encodes Gαo, the α subunit of the Go heterotrimeric G protein, which functions as a transducer downstream of GPCRs in synaptic signaling and neurodevelopment 1. As a guanine nucleotide-binding protein, GNAO1 alternates between active GTP-bound and inactive GDP-bound states, with signaling terminating through intrinsic GTPase activity that converts GTP to GDP. Go is the most abundant membrane protein in the mammalian central nervous system and mediates inhibitory signaling that decreases intracellular cAMP levels 1. GNAO1 mutations cause complex neurodevelopmental disorders characterized by epilepsy, developmental delay, and movement disorders 12. The clinical phenotype depends on mutation type: loss-of-function alleles are primarily associated with early infantile epileptic encephalopathy 17, while gain-of-function variants predominantly cause hyperkinetic movement disorders including chorea and dystonia 13. Most GNAO1 patients present with generalized hyperkinetic movements with infantile or childhood onset, severe hypotonia, and postural control disturbances 2. Deep brain stimulation effectively controls movement disorders and prevents severe paroxysmal exacerbations in patients with specific GNAO1 variants 2. Understanding genotype-phenotype correlations is essential for early diagnosis and precision medicine treatment 4.