chr3-12608835-T-C

Position:

• chr3-12608835-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The ENST00000251849.9(RAF1):​c.512A>G​(p.Lys171Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,850 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. K171T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: RAF1 ENST00000251849.9 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 6.28

Genes affected

RAF1 (HGNC:9829): (Raf-1 proto-oncogene, serine/threonine kinase) This gene is the cellular homolog of viral raf gene (v-raf). The encoded protein is a MAP kinase kinase kinase (MAP3K), which functions downstream of the Ras family of membrane associated GTPases to which it binds directly. Once activated, the cellular RAF1 protein can phosphorylate to activate the dual specificity protein kinases MEK1 and MEK2, which in turn phosphorylate to activate the serine/threonine specific protein kinases, ERK1 and ERK2. Activated ERKs are pleiotropic effectors of cell physiology and play an important role in the control of gene expression involved in the cell division cycle, apoptosis, cell differentiation and cell migration. Mutations in this gene are associated with Noonan syndrome 5 and LEOPARD syndrome 2. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in ENST00000251849.9
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), RAF1. . Gene score misZ 2.4628 (greater than the threshold 3.09). Trascript score misZ 3.4185 (greater than threshold 3.09). GenCC has associacion of gene with Noonan syndrome 5, dilated cardiomyopathy 1NN, Noonan syndrome with multiple lentigines, Noonan syndrome, cardiofaciocutaneous syndrome, familial isolated dilated cardiomyopathy, LEOPARD syndrome 2, Costello syndrome.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RAF1	NM_002880.4	c.512A>G	p.Lys171Arg	missense_variant	5/17	ENST00000251849.9	NP_002871.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RAF1	ENST00000251849.9	c.512A>G	p.Lys171Arg	missense_variant	5/17	1	NM_002880.4	ENSP00000251849	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461850 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727228

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: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 29, 2015

The p.Lys171Arg variant in RAF1 has not been previously reported in individuals with clinical features of Noonan syndrome and was absent from large population s tudies. Computational prediction tools do not provide strong support for or agai nst an impact to the protein. Lysine (Lys) at position 171 is not conserved in m ammals or evolutionarily distant species and the change to arginine (Arg) is pre sent in rhesus and fruitfly, raising the possibility that this change may be tol erated. In summary, the clinical significance of the p.Lys171Arg variant is unce rtain. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 18, 2024

Reported in an adult patient with HCM but without extracardiac manifestations compatible with Noonan syndrome (PMID: 32150461); Not observed at significant frequency in large population cohorts (gnomAD); Missense variants in this gene are a common cause of disease and they are underrepresented in the general population; In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 29493581, 32150461) -

RASopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 20, 2020

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: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. This variant has not been reported in the literature in individuals with RAF1-related conditions. ClinVar contains an entry for this variant (Variation ID: 229180). This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with arginine at codon 171 of the RAF1 protein (p.Lys171Arg). The lysine residue is highly conserved and there is a small physicochemical difference between lysine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D;.;D
Eigen	Uncertain	0.24
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.86	D;D;D
M_CAP	Uncertain	0.089	D
MetaRNN	Uncertain	0.61	D;D;D
MetaSVM	Uncertain	-0.15	T
MutationAssessor	Benign	1.1	L;L;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.78	T
PROVEAN	Benign	-1.1	N;N;N
REVEL	Uncertain	0.53
Sift	Benign	0.33	T;T;T
Sift4G	Benign	0.33	T;T;T
Polyphen		0.35	B;.;.
Vest4		0.47
MutPred		0.52		Loss of methylation at K171 (P = 0.0196);Loss of methylation at K171 (P = 0.0196);.;
MVP		0.84
MPC		0.88
ClinPred		0.87	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.41
gMVP		0.63

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: rs876657969; hg19: chr3-12650334;