18-51054970-C-G
Variant summary
Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2
The NM_005359.6(SMAD4):c.644C>G(p.Pro215Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,740 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P215A) has been classified as Uncertain significance.
Frequency
Consequence
NM_005359.6 missense
Scores
Clinical Significance
Conservation
Publications
- juvenile polyposis/hereditary hemorrhagic telangiectasia syndromeInheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp, G2P, PanelApp Australia
- Myhre syndromeInheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
- generalized juvenile polyposis/juvenile polyposis coliInheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
- juvenile polyposis syndromeInheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
- familial thoracic aortic aneurysm and aortic dissectionInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- hereditary hemorrhagic telangiectasiaInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- pulmonary arterial hypertensionInheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
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ACMG classification
Our verdict: Uncertain_significance. The variant received 2 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| SMAD4 | NM_005359.6 | c.644C>G | p.Pro215Arg | missense_variant | Exon 5 of 12 | ENST00000342988.8 | NP_005350.1 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| SMAD4 | ENST00000342988.8 | c.644C>G | p.Pro215Arg | missense_variant | Exon 5 of 12 | 5 | NM_005359.6 | ENSP00000341551.3 | ||
| ENSG00000267699 | ENST00000590722.2 | n.*820C>G | non_coding_transcript_exon_variant | Exon 8 of 9 | 2 | ENSP00000465737.1 | ||||
| ENSG00000267699 | ENST00000590722.2 | n.*820C>G | 3_prime_UTR_variant | Exon 8 of 9 | 2 | ENSP00000465737.1 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD2 exomes AF: 0.00000795 AC: 2AN: 251468 AF XY: 0.0000147 show subpopulations
GnomAD4 exome AF: 0.00000274 AC: 4AN: 1461740Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3AN XY: 727188 show subpopulations
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Uncertain:1
The p.P215R variant (also known as c.644C>G), located in coding exon 4 of the SMAD4 gene, results from a C to G substitution at nucleotide position 644. The proline at codon 215 is replaced by arginine, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. 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. -
Hereditary cancer-predisposing syndrome Uncertain:1
This missense variant replaces proline with arginine at codon 215 of the SMAD4 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with SMAD4-related disorders in the literature. This variant has been identified in 2/251468 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome Uncertain:1
- -
Juvenile polyposis syndrome Uncertain:1
This variant is present in population databases (rs777495692, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with SMAD4-related conditions. ClinVar contains an entry for this variant (Variation ID: 492485). 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 not expected to disrupt SMAD4 protein function. 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. This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 215 of the SMAD4 protein (p.Pro215Arg). -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at