chr2-39051262-A-G

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_005633.4(SOS1):​c.746T>C​(p.Ile249Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,459,024 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

Scores

14
4
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.20

Publications

1 publications found
Variant links:
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: Genomics England PanelApp, G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae)
  • 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 12 uncertain in NM_005633.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.973

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SOS1NM_005633.4 linkc.746T>C p.Ile249Thr missense_variant Exon 6 of 23 ENST00000402219.8 NP_005624.2 Q07889-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SOS1ENST00000402219.8 linkc.746T>C p.Ile249Thr missense_variant Exon 6 of 23 1 NM_005633.4 ENSP00000384675.2 Q07889-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251256
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
1459024
Hom.:
0
Cov.:
29
AF XY:
0.00
AC XY:
0
AN XY:
726056
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33414
American (AMR)
AF:
0.0000224
AC:
1
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26104
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39624
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86200
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53342
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
9.01e-7
AC:
1
AN:
1109540
Other (OTH)
AF:
0.00
AC:
0
AN:
60316
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiovascular phenotype Uncertain:1
Dec 01, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I249T variant (also known as c.746T>C), located in coding exon 6 of the SOS1 gene, results from a T to C substitution at nucleotide position 746. The isoleucine at codon 249 is replaced by threonine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

RASopathy Uncertain:1
Aug 22, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. 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 SOS1 protein function. ClinVar contains an entry for this variant (Variation ID: 543967). This missense change has been observed in individual(s) with clinical features of SOS1-related conditions (Invitae). This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 249 of the SOS1 protein (p.Ile249Thr). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.83
D;D;T
Eigen
Pathogenic
0.89
Eigen_PC
Pathogenic
0.86
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
.;D;D
M_CAP
Pathogenic
0.54
D
MetaRNN
Pathogenic
0.97
D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Uncertain
2.9
M;M;.
PhyloP100
9.2
PrimateAI
Pathogenic
0.89
D
PROVEAN
Pathogenic
-4.5
D;D;D
REVEL
Pathogenic
0.98
Sift
Uncertain
0.0010
D;D;D
Sift4G
Pathogenic
0.0010
D;D;D
Polyphen
1.0
D;D;.
Vest4
0.95
MutPred
0.81
Loss of stability (P = 0.0037);Loss of stability (P = 0.0037);Loss of stability (P = 0.0037);
MVP
0.99
MPC
1.7
ClinPred
0.98
D
GERP RS
5.7
Varity_R
0.80
gMVP
0.77
Mutation Taster
=3/97
disease causing

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

Other links and lift over

dbSNP: rs1324979194; hg19: chr2-39278403; API