1-17027849-T-C
Variant summary
Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PP3_Moderate
The NM_003000.3(SDHB):āc.440A>Gā(p.Tyr147Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000709 in 1,607,102 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y147F) has been classified as Uncertain significance.
Frequency
Consequence
NM_003000.3 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Uncertain_significance. Variant got 4 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | UniProt |
---|---|---|---|---|---|---|---|
SDHB | NM_003000.3 | c.440A>G | p.Tyr147Cys | missense_variant | 5/8 | ENST00000375499.8 | |
SDHB | NM_001407361.1 | c.386A>G | p.Tyr129Cys | missense_variant | 5/8 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|
SDHB | ENST00000375499.8 | c.440A>G | p.Tyr147Cys | missense_variant | 5/8 | 1 | NM_003000.3 | P1 |
Frequencies
GnomAD3 genomes AF: 0.0000329 AC: 5AN: 152034Hom.: 0 Cov.: 33
GnomAD3 exomes AF: 0.000104 AC: 26AN: 251178Hom.: 1 AF XY: 0.000133 AC XY: 18AN XY: 135750
GnomAD4 exome AF: 0.0000749 AC: 109AN: 1455068Hom.: 0 Cov.: 28 AF XY: 0.0000746 AC XY: 54AN XY: 724326
GnomAD4 genome AF: 0.0000329 AC: 5AN: 152034Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1AN XY: 74258
ClinVar
Submissions by phenotype
not specified Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Aug 15, 2023 | Variant summary: SDHB c.440A>G (p.Tyr147Cys) results in a non-conservative amino acid change located in the Succinate dehydogenase/fumarate reductase N-terminal domain (IPR025192) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.0001 in 251178 control chromosomes in the gnomAD database, including 1 homozygotes. The observed variant frequency is approximately 473 fold of the estimated maximal expected allele frequency for a pathogenic variant in SDHB causing Hereditary Paraganglioma-Pheochromocytoma Syndrome phenotype (2.2e-07), strongly suggesting that the variant is benign. c.440A>G has been reported in the literature in cohorts of individuals affected with Pheochromocytoma and as a VUS in settings of multigene panel testing among individuals with Pheochromocytomas and paragangliomas (PPGLs) (example, Maignan_2017, Pipitprapat_2021) and one report published a REVEL score of 0.87 for this variant (Garrett_2022). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Paraganglioma-Pheochromocytoma Syndrome. The following publications have been ascertained in the context of this evaluation (PMID: 28229225, 34309460, 34906457). Five submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as VUS (n=4) or likely benign (n=1). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. - |
Pheochromocytoma Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Baylor Genetics | Aug 24, 2019 | This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. - |
Pheochromocytoma;C0238198:Gastrointestinal stromal tumor;C1861848:Paragangliomas 4 Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Invitae | Jan 16, 2024 | This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 147 of the SDHB protein (p.Tyr147Cys). This variant is present in population databases (rs774568101, gnomAD 0.04%). This missense change has been observed in individual(s) with clinical features of SDHB-related conditions (PMID: 28229225, 34309460; Invitae). ClinVar contains an entry for this variant (Variation ID: 412466). 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 SDHB protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects SDHB function (PMID: 28229225). 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. - |
not provided Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | GeneDx | May 26, 2023 | In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Published functional studies demonstrate that this variant may disrupt SDH cellular compartmentalization (Maignan et al., 2017); Observed in individuals with pheochromocytoma or paraganglioma (Maignan et al., 2017; Garrett et al., 2022); This variant is associated with the following publications: (PMID: 28229225, 34426522, 34906457) - |
Gastrointestinal stromal tumor Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Baylor Genetics | Dec 24, 2023 | - - |
Cowden syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Mendelics | Jul 02, 2018 | - - |
Hereditary pheochromocytoma-paraganglioma Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | All of Us Research Program, National Institutes of Health | Nov 20, 2023 | This missense variant replaces tyrosine with cysteine at codon 147 of the SDHB protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). An experimental functional study have shown that this variant results in decreased SDHB mitochondrial membrane localization, and reduced SDH activity (PMID: 28229225). This variant has been reported in individuals affected with paraganglioma (PGL) or pheochromocytoma (PCC) in the literature (PMID: 28229225, 34309460, 34906457). This variant has been identified in 26/251178 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. - |
Hereditary cancer-predisposing syndrome Benign:1
Likely benign, criteria provided, single submitter | clinical testing | Ambry Genetics | Sep 21, 2021 | 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. - |
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at