chr1-17022678-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1PM2BP4

The NM_003000.3(SDHB):​c.695C>T​(p.Ala232Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,716 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

SDHB
NM_003000.3 missense

Scores

2
7
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 7.47
Variant links:
Genes affected
SDHB (HGNC:10681): (succinate dehydrogenase complex iron sulfur subunit B) This tumor suppressor gene encodes the iron-sulfur protein subunit of the succinate dehydrogenase (SDH) enzyme complex which plays a critical role in mitochondria. The SDH enzyme complex is composed of four nuclear-encoded subunits. This enzyme complex converts succinate to fumarate which releases electrons as part of the citric acid cycle, and the enzyme complex additionally provides an attachment site for released electrons to be transferred to the oxidative phosphorylation pathway. The SDH enzyme complex plays a role in oxygen-related gene regulation through its conversion of succinate, which is an oxygen sensor that stabilizes the hypoxia-inducible factor 1 (HIF1) transcription factor. Sporadic and familial mutations in this gene result in paragangliomas, pheochromocytoma, and gastrointestinal stromal tumors, supporting a link between mitochondrial dysfunction and tumorigenesis. Mutations in this gene are also implicated in nuclear type 4 mitochondrial complex II deficiency. [provided by RefSeq, Jun 2022]

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM1
In a chain Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial (size 251) in uniprot entity SDHB_HUMAN there are 96 pathogenic changes around while only 7 benign (93%) in NM_003000.3
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.31610638).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
SDHBNM_003000.3 linkuse as main transcriptc.695C>T p.Ala232Val missense_variant 7/8 ENST00000375499.8 NP_002991.2
SDHBNM_001407361.1 linkuse as main transcriptc.641C>T p.Ala214Val missense_variant 7/8 NP_001394290.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
SDHBENST00000375499.8 linkuse as main transcriptc.695C>T p.Ala232Val missense_variant 7/81 NM_003000.3 ENSP00000364649 P1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000358
AC:
9
AN:
251438
Hom.:
0
AF XY:
0.0000294
AC XY:
4
AN XY:
135898
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000260
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS 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:
0.00000684
AC:
10
AN:
1461716
Hom.:
0
Cov.:
31
AF XY:
0.00000550
AC XY:
4
AN XY:
727168
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32
Bravo
AF:
0.00000756
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Pheochromocytoma;C0238198:Gastrointestinal stromal tumor;C1861848:Paragangliomas 4 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 31, 2024This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 232 of the SDHB protein (p.Ala232Val). This variant is present in population databases (rs746224555, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with SDHB-related conditions. ClinVar contains an entry for this variant (Variation ID: 459164). 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 SDHB protein function with a negative predictive value of 80%. 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. -
Paragangliomas 4 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingBaylor GeneticsApr 10, 2020This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxDec 19, 2023In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Gastrointestinal stromal tumor Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingBaylor GeneticsDec 30, 2023- -
Hereditary cancer-predisposing syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsAug 01, 2023The p.A232V variant (also known as c.695C>T), located in coding exon 7 of the SDHB gene, results from a C to T substitution at nucleotide position 695. The alanine at codon 232 is replaced by valine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.0026
T
BayesDel_noAF
Uncertain
0.050
CADD
Uncertain
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.72
D
Eigen
Benign
0.14
Eigen_PC
Uncertain
0.28
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Uncertain
0.089
D
MetaRNN
Benign
0.32
T
MetaSVM
Uncertain
0.69
D
MutationAssessor
Benign
2.0
M
MutationTaster
Benign
1.0
D
PrimateAI
Benign
0.48
T
PROVEAN
Benign
-2.0
N
REVEL
Uncertain
0.45
Sift
Benign
0.26
T
Sift4G
Benign
0.065
T
Polyphen
0.030
B
Vest4
0.52
MutPred
0.25
Loss of ubiquitination at K233 (P = 0.0637);
MVP
0.93
MPC
0.22
ClinPred
0.24
T
GERP RS
4.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.19
gMVP
0.70

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs746224555; hg19: chr1-17349173; API