chr7-140778053-C-A

Position:

• chr7-140778053-C-A

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2 PP3 PP2 PM6_Strong PS4 PS3

This summary comes from the ClinGen Evidence Repository: The c.1455G>T (p.Leu485Phe) variant in BRAF is absent from gnomAD (PM2). It has been detected in at least 5 patients with clinical features of a RASopathy, 2 of which were reported as unconfirmed de novo cases (PS4; PM6_Strong; PMIDs: 18039235, 28524057, SCV000832735.1, SCV000204150.4, SCV000965953.1, Otto-von-Guericke-Universität Magdeburg internal communication). In vitro functional studies provide some evidence that the p.L485F variant may impact protein function (PS3; PMID:18413255). 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 this variant may affect the protein (PP3). In summary, this variant meets criteria to be classified as pathogenic for RASopathies in an autosomal dominant manner. Rasopathy-specific ACMG/AMP criteria applied (PMID:29493581): PS4, PM6_Strong, PS3, PM2, PP2, PP3. LINK:https://erepo.genome.network/evrepo/ui/classification/CA280060/MONDO:0021060/004

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRAF NM_001374258.1 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:6 U:1
• Conservation: PhyloP100: 5.00

Genes affected

BRAF (HGNC:1097): (B-Raf proto-oncogene, serine/threonine kinase) This gene encodes a protein belonging to the RAF family of serine/threonine protein kinases. This protein plays a role in regulating the MAP kinase/ERK signaling pathway, which affects cell division, differentiation, and secretion. Mutations in this gene, most commonly the V600E mutation, are the most frequently identified cancer-causing mutations in melanoma, and have been identified in various other cancers as well, including non-Hodgkin lymphoma, colorectal cancer, thyroid carcinoma, non-small cell lung carcinoma, hairy cell leukemia and adenocarcinoma of lung. Mutations in this gene are also associated with cardiofaciocutaneous, Noonan, and Costello syndromes, which exhibit overlapping phenotypes. A pseudogene of this gene has been identified on the X chromosome. [provided by RefSeq, Aug 2017]

(HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRAF	NM_001374258.1	c.1575G>T	p.Leu525Phe	missense_variant	13/20	ENST00000644969.2
BRAF	NM_004333.6	c.1455G>T	p.Leu485Phe	missense_variant	12/18	ENST00000646891.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRAF	ENST00000644969.2	c.1575G>T	p.Leu525Phe	missense_variant	13/20		NM_001374258.1
BRAF	ENST00000646891.2	c.1455G>T	p.Leu485Phe	missense_variant	12/18		NM_004333.6	P4
	ENST00000700122.1	n.502+3185C>A		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6 Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

RASopathy Pathogenic:2

Pathogenic, reviewed by expert panel	curation	ClinGen RASopathy Variant Curation Expert Panel	Feb 27, 2020	The c.1455G>T (p.Leu485Phe) variant in BRAF is absent from gnomAD (PM2). It has been detected in at least 5 patients with clinical features of a RASopathy, 2 of which were reported as unconfirmed de novo cases (PS4; PM6_Strong; PMIDs: 18039235, 28524057, SCV000832735.1, SCV000204150.4, SCV000965953.1, Otto-von-Guericke-Universität Magdeburg internal communication). In vitro functional studies provide some evidence that the p.L485F variant may impact protein function (PS3; PMID: 18413255). 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 this variant may affect the protein (PP3). In summary, this variant meets criteria to be classified as pathogenic for RASopathies in an autosomal dominant manner. Rasopathy-specific ACMG/AMP criteria applied (PMID:29493581): PS4, PM6_Strong, PS3, PM2, PP2, PP3. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 08, 2021	ClinVar contains an entry for this variant (Variation ID: 177844). For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects BRAF function (PMID: 16439621, 16474404, 18413255, 25348715). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). This missense change has been observed in individuals with cardio-facio-cutaneous syndrome (PMID: 16439621, 16474404, 18039235, 19206169, 28524057). This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with phenylalanine at codon 485 of the BRAF protein (p.Leu485Phe). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and phenylalanine. -

Noonan syndrome;C1275081:Cardio-facio-cutaneous syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Oct 21, 2014

The c.1455G>T (Leu485Phe) variant in BRAF has been previously identified in one individual with clinical features of a Cardio-facio-cutaneous syndrome (LMM unpu blished data). It was absent from large population studies (http://evs.gs.washin gton.edu/EVS/). In addition, a different variant with the same amino acid change (c.1455G>C) was identified in four individuals with clinical features of a RASo pathy (Niihori 2006, Rodriguez-Viciana 2006, LMM unpublished data). In vitro fu nctional studies provide some evidence that the Leu485Phe variant may impact pro tein function by increasing its kinase activity (Rodriguez-Viciana 2008). Howeve r, these types of assays may not accurately represent biological function. In s ummary, this variant meets our criteria to be classified as pathogenic (http://p cpgmwww.partners.org/personalizedmedicince/LMM). -

Cardiofaciocutaneous syndrome 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory of Medical Genetics, National & Kapodistrian University of Athens

May 16, 2024

PS1, PS4, PM1, PM2, PP3, PP5- The variant has been reported in ClinVar as Pathogenic by other laboratories (Variation ID: 177844). In silico prediction tools estimated that the variant could be damaging for the protein function/stracture. It is not present in population databases (gnomAD no frequency). -

Cardio-facio-cutaneous syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Sep 11, 2019

Variant summary: BRAF c.1455G>T (p.Leu485Phe) results in a non-conservative amino acid change located in the Serine-threonine/tyrosine-protein kinase, catalytic domain (IPR001245) of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251326 control chromosomes (gnomAD). The variant, c.1455G>T, has been reported in the literature in individuals affected with Cardiofaciocutaneous Syndrome (Rodriguez-Viciana_2006, Sato_2017). Another variant (c.1455G>C) leading to the same protein change (p.Leu485Phe) has also been observed in individuals affected with Cardiofaciocutaneous Syndrome including one de novo occurrence (Niihori_2006, Sarkozy_2009). These data indicate that the variant is likely to be associated with disease. At least two publications reported experimental evidence evaluating an impact on protein function and showed increased BRAF activity (Niihori_2006, Rodriguez-Viciana_2006). One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as likely pathogenic. Another variant affecting the same codon, p.L485S, has been reported to associate with Cardiofaciocutaneous Syndrome too. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Jan 23, 2023

Reported in probands with clinical features of cardio-facio-cutaneous (CFC) syndrome (Yoon et al., 2007; Sato et al., 2017; Mohan et al., 2022); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Missense variants in this gene are often considered pathogenic (HGMD); This variant is associated with the following publications: (PMID: 34358384, 30406758, 18039235, 28524057) -

Noonan syndrome Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Service de Génétique Moléculaire, Hôpital Robert Debré

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.85	.;.;D;.
Eigen	Uncertain	0.20
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Benign	0.077	D
MetaRNN	Pathogenic	0.94	D;D;D;D
MetaSVM	Benign	-0.84	T
MutationAssessor	Benign	1.1	.;.;L;.
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Benign	-1.8	.;.;.;N
REVEL	Pathogenic	0.76
Sift	Benign	0.20	.;.;.;T
Polyphen		0.26	.;.;B;.
MutPred		0.86		Gain of catalytic residue at L485 (P = 0.046);.;Gain of catalytic residue at L485 (P = 0.046);.;
MVP		0.99
MPC		2.1
ClinPred		0.99	D
GERP RS		4.1
Varity_R		0.95
gMVP		0.81

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs180177036; hg19: chr7-140477853; COSMIC: COSV56396779; COSMIC: COSV56396779;