rs775105134

chr2-39022578-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_005633.4(SOS1):c.1850T>C(p.Met617Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,008 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SOS1 NM_005633.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.20

Genes affected

SOS1 (HGNC:11187): (SOS Ras/Rac guanine nucleotide exchange factor 1) This gene encodes a protein that is a guanine nucleotide exchange factor for RAS proteins, membrane proteins that bind guanine nucleotides and participate in signal transduction pathways. GTP binding activates and GTP hydrolysis inactivates RAS proteins. The product of this gene may regulate RAS proteins by facilitating the exchange of GTP for GDP. Mutations in this gene are associated with gingival fibromatosis 1 and Noonan syndrome type 4. [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 1 benign, 6 uncertain in NM_005633.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.778

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SOS1	NM_005633.4	c.1850T>C	p.Met617Thr	missense_variant	10/23	ENST00000402219.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SOS1	ENST00000402219.8	c.1850T>C	p.Met617Thr	missense_variant	10/23	1	NM_005633.4	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000400 AC: 1 AN: 250180 Hom.: 0 AF XY: 0.00000739 AC XY: 1 AN XY: 135294

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000545

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460008 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726414

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: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

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

Invitae

Oct 19, 2022

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 missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 40688). This variant has not been reported in the literature in individuals affected with SOS1-related conditions. This variant is present in population databases (rs775105134, gnomAD 0.006%). This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 617 of the SOS1 protein (p.Met617Thr). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.58
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	0.090
Cadd	Uncertain	25
Dann	Uncertain	0.98
DEOGEN2	Uncertain	0.52	D;D;T
Eigen	Benign	-0.046
Eigen_PC	Benign	0.18
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Benign	0.021	T
MetaRNN	Pathogenic	0.78	D;D;D
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.2	L;L;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Uncertain	-3.5	D;D;D
REVEL	Uncertain	0.36
Sift	Benign	0.14	T;T;T
Sift4G	Benign	0.067	T;T;T
Polyphen		0.050	B;B;.
Vest4		0.93
MutPred		0.51		Gain of relative solvent accessibility (P = 0.0289);Gain of relative solvent accessibility (P = 0.0289);Gain of relative solvent accessibility (P = 0.0289);
MVP		0.61
MPC		0.83
ClinPred		0.48	T
GERP RS		5.8
Varity_R		0.62
gMVP		0.77

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: rs775105134; hg19: chr2-39249719;