NM_005633.4:c.1655G>T
Variant summary
Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PP3PP2PS4_ModeratePM1_Strong
This summary comes from the ClinGen Evidence Repository: The c.1655G>T (p.Arg552Met) variant has been identified in at least 3 independent occurrences in patients with clinical features of a RASopathy (PS4_Moderate; GeneDx internal data; GTR Lab IDs 26957; SCV000565586.5 PMID:21387466). his AA residue has been specified as a hotspot for variation. These variants would have received PM5_Strong but the RAS EP decided that PM1 and PM5 cannot be used simultaneously and therefore this rule has been upgraded with expert judgement (PM1_Strong). Computational prediction tools and conservation analysis suggest that the p.Arg552Met variant may impact the protein (PP3). The variant is located in the SOS1 gene, which has been defined by the ClinGen RASopathy Expert Panel as a gene with a low rate of benign missense variants and pathogenic missense variants are common (PP2; PMID:29493581). In summary, this variant meets criteria to be classified as likely pathogenic for RASopathies in an autosomal dominant manner. RASopathy-specific ACMG/AMP criteria applied (PMID:29493581): PS4_Moderate, PM1_Strong, PP2, PP3. LINK:https://erepo.genome.network/evrepo/ui/classification/CA16616762/MONDO:0021060/004
Frequency
Consequence
NM_005633.4 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Likely_pathogenic. Variant got 8 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD3 exomes AF: 0.00000399 AC: 1AN: 250906Hom.: 0 AF XY: 0.00000737 AC XY: 1AN XY: 135598
GnomAD4 exome AF: 0.00000137 AC: 2AN: 1461578Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1AN XY: 727092
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
not provided Pathogenic:2
PS4, PM1_Strong, PP2, PP3 -
In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 24803665, 30417923, 31219622, 20648242, 29493581, 17143282, 21387466, 12628188) -
Noonan syndrome Pathogenic:1
The Arg552Met variant in SOS1 has been reported in the literature in two patients with clinical features of Noonan Syndrome (Lepri 2011). Furthermore, several other amino acid changes at this position have been reported in association with Noonan syndrome (Arg552Ser, Arg552Lys, Arg552Thr, Arg552Gly; Beneteau 2009, Lepri 2011, LMM unreported data). This variant was also shown to be absent from 600 control chromosomes and has not been identified in large and broad populations by the NHLBI Exome Sequencing Project (Lepri 2011, http://evs.gs.washington.edu/EVS/). Computational analyses (biochemical amino acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) suggest that the Arg552Met variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, this variant is likely pathogenic, though additional studies are required to fully establish its clinical significance. -
Noonan syndrome and Noonan-related syndrome Pathogenic:1
The c.1655G>T (p.Arg552Met) variant has been identified in at least 3 independent occurrences in patients with clinical features of a RASopathy (PS4_Moderate; GeneDx internal data; GTR Lab IDs 26957; SCV000565586.5 PMID: 21387466). his AA residue has been specified as a hotspot for variation. These variants would have received PM5_Strong but the RAS EP decided that PM1 and PM5 cannot be used simultaneously and therefore this rule has been upgraded with expert judgement (PM1_Strong). Computational prediction tools and conservation analysis suggest that the p.Arg552Met variant may impact the protein (PP3). The variant is located in the SOS1 gene, which has been defined by the ClinGen RASopathy Expert Panel as a gene with a low rate of benign missense variants and pathogenic missense variants are common (PP2; PMID: 29493581). In summary, this variant meets criteria to be classified as likely pathogenic for RASopathies in an autosomal dominant manner. RASopathy-specific ACMG/AMP criteria applied (PMID:29493581): PS4_Moderate, PM1_Strong, PP2, PP3. -
RASopathy Pathogenic:1
This sequence change replaces arginine, which is basic and polar, with methionine, which is neutral and non-polar, at codon 552 of the SOS1 protein (p.Arg552Met). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This missense change has been observed in individuals with clinical features of Noonan syndrome (PMID: 21387466, 30417923, 31219622; Invitae). ClinVar contains an entry for this variant (Variation ID: 40681). 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 with a positive predictive value of 95%. This variant disrupts the p.Arg552 amino acid residue in SOS1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 17143282, 17586837, 18854871, 21340158, 21387466, 23487764, 25073238). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at