NM_002524.5:c.35G>T (NP_002515.1:p.Gly12Val) is a missense variant in NRAS exon 2.1 G12V is a well-established pathogenic substitution at a critical residue within the P-loop GTP-binding domain (amino acids 10-17).2 This variant has been reported in ClinVar as Pathogenic by 6 clinical laboratories and Likely pathogenic by 1 (ClinVarID 40470), and is a recurrent somatic alteration in human cancers (COSMIC n=183; OncoKB: Oncogenic).3 The variant is essentially absent from population databases (gnomAD v2.1: 0/251,484; v4.1: 1/1,613,974; gnomAD-Canada: absent).4 G12V has been functionally characterized as an activating alteration in two VCEP-approved assay types (RAS Activation and MEK Activation), supporting a gain-of-function mechanism consistent with RASopathy pathogenesis.5 Multiple different pathogenic missense variants exist at the same codon (G12D, G12S, G12C, G12A, G12R), supporting the functional importance of this residue.6 In silico predictors support a deleterious effect (REVEL 0.787; BayesDel 0.315; SpliceAI delta 0.00).7 Criteria met: PS1 (Strong), PS3 (Moderate), PM1 (Moderate), PM5 (Strong), PM2 (Supporting), PP3 (Supporting).8