rs727504295

Variant names:

• chr2-39023106-C-T
• rs727504295
• NM_005633.4:c.1322G>A

Variant summary

Our verdict is Pathogenic. The variant received 20 ACMG points: 20P and 0B. PS3 PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_005633.4(SOS1):​c.1322G>A​(p.Cys441Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,358 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 Pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000209111: Published functional studies demonstrate normal to increased SOS1 activity (Gureasko et al., 2010, Smith et al., 2013)" and additional evidence is available in ClinVar. The gene SOS1 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SOS1 NM_005633.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 7.79
• Publications: 15 publications found

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]

SOS1 Gene-Disease associations (from GenCC):

• Noonan syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Noonan syndrome 4

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, PanelApp Australia, Genomics England PanelApp
• fibromatosis, gingival, 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• hereditary gingival fibromatosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• cardiofaciocutaneous syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• Costello syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• Noonan syndrome with multiple lentigines

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• Noonan syndrome-like disorder with loose anagen hair

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Specifications for SOS1 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 20 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV000209111: Published functional studies demonstrate normal to increased SOS1 activity (Gureasko et al., 2010, Smith et al., 2013); SCV001477572: the variant also exhibits increased PIP2-dependent nucleotide exchange rates (Gureasko 2010).; SCV004804324: At least one publication reports experimental evidence evaluating an impact on protein function (Gureasko_2009). PMID:19077116
• PM1: In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 10 uncertain in NM_005633.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.97
• PP5: Variant 2-39023106-C-T is Pathogenic according to our data. Variant chr2-39023106-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 40673.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005633.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SOS1	NM_005633.4	MANE Select	c.1322G>A	p.Cys441Tyr	missense	Exon 10 of 23	NP_005624.2
	SOS1	NM_001382394.1		c.1301G>A	p.Cys434Tyr	missense	Exon 10 of 23	NP_001369323.1
	SOS1	NM_001382395.1		c.1322G>A	p.Cys441Tyr	missense	Exon 10 of 22	NP_001369324.1	G5E9C8

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SOS1	ENST00000402219.8	TSL:1 MANE Select	c.1322G>A	p.Cys441Tyr	missense	Exon 10 of 23	ENSP00000384675.2	Q07889-1
	SOS1	ENST00000395038.6	TSL:5	c.1322G>A	p.Cys441Tyr	missense	Exon 10 of 22	ENSP00000378479.2	G5E9C8
	SOS1	ENST00000913801.1		c.1322G>A	p.Cys441Tyr	missense	Exon 10 of 22	ENSP00000583860.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461358 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726978

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26112

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.00 AC: 0 AN: 86222

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53350

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111648

Other (OTH) AF: 0.00 AC: 0 AN: 60384

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0448430), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (3)
2	-	-	Noonan syndrome 4 (2)
2	-	-	RASopathy (2)
1	-	-	Noonan syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.49	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Uncertain	0.72	D
MutationAssessor	Uncertain	2.8	M
PhyloP100		7.8
PrimateAI	Pathogenic	0.95	D
PROVEAN	Pathogenic	-9.9	D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.84		Loss of catalytic residue at M446 (P = 0.0424)
MVP		0.96
MPC		2.0
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.98
gMVP		0.94
Mutation Taster		=2/98	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs727504295; hg19: chr2-39250247; COSMIC: COSV67677222; COSMIC: COSV67677222;