rs797045167

Positions:

• chr14-50182521-A-G
• chr14-50182521-A-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1 PM2 PM5 PP3_Moderate PP5_Very_Strong

The NM_006939.4(SOS2):​c.800T>C​(p.Met267Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M267K) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SOS2 NM_006939.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 9.32

Genes affected

SOS2 (HGNC:11188): (SOS Ras/Rho guanine nucleotide exchange factor 2) This gene encodes a regulatory protein that is involved in the positive regulation of ras proteins. Mutations in this gene are associated with Noonan Syndrome-9. [provided by RefSeq, Jul 2016]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PM1: In a domain DH (size 190) in uniprot entity SOS2_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_006939.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr14-50182521-A-T is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.884
• PP5: Variant 14-50182521-A-G is Pathogenic according to our data. Variant chr14-50182521-A-G is described in ClinVar as [Pathogenic]. Clinvar id is 373114.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr14-50182521-A-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SOS2	NM_006939.4	c.800T>C	p.Met267Thr	missense_variant	6/23	ENST00000216373.10	NP_008870.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SOS2	ENST00000216373.10	c.800T>C	p.Met267Thr	missense_variant	6/23	1	NM_006939.4	ENSP00000216373	P1
SOS2	ENST00000543680.5	c.800T>C	p.Met267Thr	missense_variant	6/22	1		ENSP00000445328
SOS2	ENST00000556469.5	n.567T>C		non_coding_transcript_exon_variant	5/5	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Noonan syndrome 9 Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Department of Human Genetics, University Hospital Magdeburg	Jul 02, 2020	This variant has been previously reported as pathogenic (PS1). It is absent from gnomAD (PM2). The variant is assumed to be de novo, but without confirmation of paternity and maternity (PM6). The REVEL Score of this variant is 0.868 (PP3) and the variant has been classified as pathogenic in ClinVar (PP5). -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jun 24, 2023	For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Met267 amino acid residue in SOS2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 25795793, 26173643). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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 expected to disrupt SOS2 protein function. ClinVar contains an entry for this variant (Variation ID: 373114). This missense change has been observed in individual(s) with clinical features of Noonan syndrome (Invitae). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 267 of the SOS2 protein (p.Met267Thr). -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	-	- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Nov 17, 2017

The M267T variant in the SOS2 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. However, a different missense variant in the same residue, M267K, was identified as a de novo change in a patient with Noonan syndrome (Yamamoto et al., 2015). A second missense variant in the same residue, M267R, was identified in two individuals with Noonan syndrome, and functional studies of M267R indicate that it promotes enhanced phosphorylation of ERK (Cordeddu et al., 2015). The M267T variant was not observed in approximately 6500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The M267T variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species, and in silico analysis predicts this variant is probably damaging to the protein structure/function. We interpret M267T as a pathogenic variant -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.58	D;.
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.92	D;D
M_CAP	Pathogenic	0.48	D
MetaRNN	Pathogenic	0.88	D;D
MetaSVM	Uncertain	0.75	D
MutationAssessor	Uncertain	2.7	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Pathogenic	-4.6	D;D
REVEL	Pathogenic	0.87
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.025	D;D
Polyphen		0.34	B;.
Vest4		0.91
MutPred		0.61		Gain of glycosylation at M267 (P = 0.0162);Gain of glycosylation at M267 (P = 0.0162);
MVP		0.98
MPC		1.4
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.75
gMVP		0.75

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.11		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: rs797045167; hg19: chr14-50649239; COSMIC: COSV53566429; COSMIC: COSV53566429;