GNAO1 and epilepsy: Interestingly, Feng et al. reported a biochemical analysis of 15 different GNAO1 mutant alleles that revealed that loss-of-function (LOF) GNAO1 alleles were associated with epilepsy based on an inability to suppress cAMP production, whereas gain-of-function (GOF) or normal-function (NF) GNAO1 alleles were associated with MDs (9).