rs145988618
Variant summary
Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2
The NM_005359.6(SMAD4):c.354G>A(p.Ala118Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00372 in 1,613,918 control chromosomes in the GnomAD database, including 17 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).
Frequency
Consequence
NM_005359.6 synonymous
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Benign. Variant got -21 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
SMAD4 | NM_005359.6 | c.354G>A | p.Ala118Ala | synonymous_variant | Exon 3 of 12 | ENST00000342988.8 | NP_005350.1 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
SMAD4 | ENST00000342988.8 | c.354G>A | p.Ala118Ala | synonymous_variant | Exon 3 of 12 | 5 | NM_005359.6 | ENSP00000341551.3 | ||
ENSG00000267699 | ENST00000590722.2 | n.*377G>A | non_coding_transcript_exon_variant | Exon 4 of 9 | 2 | ENSP00000465737.1 | ||||
ENSG00000267699 | ENST00000590722.2 | n.*377G>A | 3_prime_UTR_variant | Exon 4 of 9 | 2 | ENSP00000465737.1 |
Frequencies
GnomAD3 genomes AF: 0.00256 AC: 390AN: 152108Hom.: 0 Cov.: 33
GnomAD3 exomes AF: 0.00276 AC: 693AN: 251432Hom.: 3 AF XY: 0.00262 AC XY: 356AN XY: 135890
GnomAD4 exome AF: 0.00384 AC: 5613AN: 1461694Hom.: 17 Cov.: 32 AF XY: 0.00374 AC XY: 2716AN XY: 727174
GnomAD4 genome AF: 0.00256 AC: 390AN: 152224Hom.: 0 Cov.: 33 AF XY: 0.00253 AC XY: 188AN XY: 74426
ClinVar
Submissions by phenotype
not provided Benign:7
- -
- -
- -
- -
- -
SMAD4: BP4, BP7, BS1, BS2 -
- -
not specified Benign:6
- -
- -
This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
- -
- -
- -
Hereditary cancer-predisposing syndrome Benign:4
- -
- -
- -
BS2_Supporting, BP4, BP7 c.354G>A located in exon 11 of the SMAD4 gene affects a non-conserved nucleotide, resulting in no amino acid change, p.(Ala464=) (BP7). This variant allele was found in 540/118134 alleles (3 homozygotes), with a filtered allele frequency of 0.41% at 99% confidence, within the European (non-Finnish) population in the gnomAD v2.1.1 database (non-cancer data set) (BS2_Supporting). The SpliceAI algorithm predicts no significant impact on splicing (BP4). To our knowledge, no well-established functional studies have been reported for this variant. This variant has been reported in controls and patients affected with multiple adenomatous polyposis, early-onset colorectal cancer, juvenile polyposis syndrome, endometrial cancer and AFAP (PMID: 22875147, 16436638, internal data). It has been reported in the ClinVar database (12x benign and 10x likely benign) and in the LOVD database (2x benign and 3x likely benign). Based on currently available information, the variant c.354G>A should be considered a likely benign variant. -
Myhre syndrome Benign:2
- -
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Carcinoma of colon Benign:1
The SMAD4 p.Ala118= variant was identified in 1 of 140 proband chromosomes (frequency: 0.007) from individuals or families with Juvenile polyposis syndrome (Pyatt 2006). The variant was also identified in dbSNP (ID: rs145988618) as "With other allele", ClinVar (classified as benign by Invitae, GeneDx, and ARUP; as likely benign by 7 submitters), Cosmic (2X in large intestine tissue), LOVD 3.0 (4x as benign or likely benign), and in ARUP Laboratories (as benign). The variant was identified in control databases in 768 of 277174 chromosomes (3 homozygous) at a frequency of 0.003 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: African in 23 of 24032 chromosomes (freq: 0.0009), Other in 13 of 6462 chromosomes (freq: 0.002), Latino in 21 of 34418 chromosomes (freq: 0.0006), European in 572 of 126678 chromosomes (freq: 0.005), Ashkenazi Jewish in 3 of 10150 chromosomes (freq: 0.0003), Finnish in 132 of 25786 chromosomes (freq: 0.005), and South Asian in 4 of 30782 chromosomes (freq: 0.0001); it was not observed in the East Asian, population. The p.Ala118= variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. In addition, in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -
Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1
This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Generalized juvenile polyposis/juvenile polyposis coli Benign:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome Benign:1
This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Juvenile polyposis syndrome Benign:1
- -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at