7-140734635-T-C

Position:

• chr7-140734635-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001374258.1(BRAF):​c.2383A>G​(p.Ile795Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I795M) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: BRAF NM_001374258.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.02

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), BRAF. . Gene score misZ 3.7208 (greater than the threshold 3.09). Trascript score misZ 4.9008 (greater than threshold 3.09). GenCC has associacion of gene with LEOPARD syndrome 3, anaplastic astrocytoma, Noonan syndrome with multiple lentigines, cardiofaciocutaneous syndrome 1, Noonan syndrome, cardiofaciocutaneous syndrome, Costello syndrome, Noonan syndrome 7.
• BP4: Computational evidence support a benign effect (MetaRNN=0.28508615).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRAF	NM_001374258.1	c.2383A>G	p.Ile795Val	missense_variant	19/20	ENST00000644969.2
BRAF	NM_004333.6	c.2263A>G	p.Ile755Val	missense_variant	18/18	ENST00000646891.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRAF	ENST00000644969.2	c.2383A>G	p.Ile795Val	missense_variant	19/20		NM_001374258.1
BRAF	ENST00000646891.2	c.2263A>G	p.Ile755Val	missense_variant	18/18		NM_004333.6	P4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461880 Hom.: 0 Cov.: 33 AF XY: 0.00000413 AC XY: 3 AN XY: 727236

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

RASopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 25, 2022

This variant is not present in population databases (gnomAD no frequency). This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 755 of the BRAF protein (p.Ile755Val). This variant has not been reported in the literature in individuals affected with BRAF-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRAF protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Uncertain	0.036	T
BayesDel_noAF	Benign	-0.19
CADD	Uncertain	24
DANN	Benign	0.83
DEOGEN2	Benign	0.27	.;.;T;.
Eigen	Benign	-0.064
Eigen_PC	Benign	0.17
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.93	D;D;D;D
M_CAP	Benign	0.020	T
MetaRNN	Benign	0.29	T;T;T;T
MetaSVM	Benign	-0.82	T
MutationAssessor	Benign	0.34	.;.;N;.
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.76	T
REVEL	Uncertain	0.31
Polyphen		0.46	.;.;P;.
MutPred		0.26		Gain of catalytic residue at I755 (P = 0.0192);.;Gain of catalytic residue at I755 (P = 0.0192);.;
MVP		0.72
MPC		1.2
ClinPred		0.51	D
GERP RS		5.8
Varity_R		0.095
gMVP		0.29

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr7-140434435; COSMIC: COSV56334241;