The c.1454T>C (p.Leu485Ser) variant in BRAF is absent from gnomAD (PM2). It has been identified in at least 4 patients clinically diagnosed with Cardiofaciocutaneous syndrome (CFC) (PS4_Moderate; 18039235, 21871821, 20395089, SCV000197150.4). The variant is located in the BRAF gene, which has been defined by the ClinGen RASopathy Expert Panel as a gene with a low rate of benign missense variants and pathogenic missense variants are common (PP2; PMID: 29493581). Additionally, computational prediction tools and conservation analysis suggest that p.Leu485Ser may affect the protein (PP3). Two different pathogenic missense variants have been previously identified at this codon of BRAF, each resulting in p.Leu485Phe, which supports that this residue may be critical to the function of the protein (PM5; ClinVar 177844, 13975). A functional assay has been performed on this variant, but given that it is not currently an approved assay outlined by the RASopathy VCEP, it has not been assessed for PS3 at this time (PMID:16474404). In summary, this variant meets criteria to be classified as likely pathogenic for RASopathies in an autosomal dominant manner. RASopathy-specific ACMG/AMP criteria applied (PMID:29493581): PM2, PS4_Moderate, PP2, PP3, PM5.