NM_003000.3:c.640C>T

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 19 ACMG points: 19P and 0B. PVS1PM2PP3PP5_Very_Strong

The NM_003000.3(SDHB):c.640C>T(p.Gln214*) variant causes a stop gained, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 33)

Consequence

SDHB
NM_003000.3 stop_gained, splice_region

Scores

Splicing: ADA: 0.9993

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:11

Conservation

PhyloP100: 8.91

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]

SDHB links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 19 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

PP5

Variant 1-17023975-G-A is Pathogenic according to our data. Variant chr1-17023975-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 230243.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-17023975-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHB	NM_003000.3 link	c.640C>T	p.Gln214*	stop_gained, splice_region_variant	Exon 6 of 8	ENST00000375499.8	NP_002991.2	P21912
SDHB	NM_001407361.1 link	c.586C>T	p.Gln196*	stop_gained, splice_region_variant	Exon 6 of 8		NP_001394290.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
SDHB	ENST00000375499.8 link	c.640C>T	p.Gln214*	stop_gained, splice_region_variant	Exon 6 of 8	1	NM_003000.3	ENSP00000364649.3	P21912
SDHB	ENST00000491274.6 link	c.598C>T	p.Gln200*	stop_gained, splice_region_variant	Exon 6 of 8	5		ENSP00000480482.2	A0A087WWT1
SDHB	ENST00000463045.3 link	c.469C>T	p.Gln157*	stop_gained, splice_region_variant	Exon 6 of 8	3		ENSP00000481376.2	A0A087WXX8
SDHB	ENST00000485515.5 link	n.574C>T		splice_region_variant, non_coding_transcript_exon_variant	Exon 6 of 7	5		ENSP00000519322.1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

Cov.:

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:11

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Paragangliomas 4

Pathogenic:4

Oct 13, 2015

Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 15, 2023

Myriad Genetics, Inc.

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered pathogenic. This variant creates a termination codon and is predicted to result in premature protein truncation. -

Jan 03, 2022

3billion

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Stop-gained (nonsense): predicted to result in a loss or disruption of normal protein function through nonsense-mediated decay (NMD) or protein truncation. Multiple pathogenic variants are reported downstream of the variant (PVS1_VS). It is not observed in the gnomAD v2.1.1 dataset (PM2_M). The variant has been reported at least twice as pathogenic/likely pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000230243, PMID:17943698). Therefore, this variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. -

Aug 28, 2019

New York Genome Center

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The inherited c.640C>T (p.Gln214Ter) variant identified in the SDHB gene leads to the premature termination of the protein at amino acid 214/281 (coding exon 6/8) and is predicted to undergo nonsense mediated decay. This variant is absent from gnomAD and ExAC, suggesting it is not a common benign variant in the populations represented in these databases. This variant is classified as Pathogenic in ClinVar (VarID:230243), and has been reported in the literature in individuals with early onset Pheochromocytomas [PMID: 17943698; PMID: 19694205]. Given its deleterious nature, its absence in population databases, and its observation in affected individuals in the literature, the c.640C>T (p.Gln214Ter) variant identified in the SDHB gene is reported here as Likely Pathogenic. -

Hereditary pheochromocytoma-paraganglioma

Pathogenic:2

Nov 02, 2023

All of Us Research Program, National Institutes of Health

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant changes 1 nucleotide in exon 6 of the SDHB gene, creating a premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. This variant has been reported in individuals affected with hereditary paranganglioma-pheochromocytoma syndrome (PMID: 17943698, 19694205, 32460727, 34654328). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of SDHB function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -

Mar 26, 2020

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: SDHB c.640C>T (p.Gln214X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay. The variant was absent in 251290 control chromosomes. c.640C>T has been reported in the literature in individuals affected with Hereditary Paraganglioma-Pheochromocytoma Syndrome (Reusch_2007, Kim_2009). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Pheochromocytoma;C1847319:Carney-Stratakis syndrome;C1861848:Paragangliomas 4

Pathogenic:1

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Pheochromocytoma;C0238198:Gastrointestinal stromal tumor;C1861848:Paragangliomas 4

Pathogenic:1

Nov 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Gln214*) in the SDHB gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SDHB are known to be pathogenic (PMID: 19454582, 19802898). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with pheochromocytoma and paraganglioma (PMID: 17943698, 19694205). ClinVar contains an entry for this variant (Variation ID: 230243). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. For these reasons, this variant has been classified as Pathogenic. -

not provided

Pathogenic:1

Nov 13, 2024

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 19694205, 25525159, 17943698, 28873162, 30787465, 36113475, 35988656) -

Gastrointestinal stromal tumor

Pathogenic:1

Jun 05, 2022

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome

Pathogenic:1

Jul 27, 2022

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Q214* pathogenic mutation (also known as c.640C>T) located in coding exon 6 of the SDHB gene, results from a C to T substitution at nucleotide position 640. This changes the amino acid from a glutamine to a stop codon within coding exon 6. This mutation was first described in a 40-year-old Chinese female with a recurrent pheochromocytoma in the left adrenal gland. The patient's first pheochromocytoma had been removed 18 years prior to this study (Reusch J et al. Exp Clin Endocrinol Diabetes. 2007;115(9):616-8). It was also identified in a 15 year-old female with hypertension due to a functional abdominal paraganglioma (Kim MS et al. J. Pediatr. Endocrinol. Metab. 2009 Jun; 22(6):565-71). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.66

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.2

Eigen_PC

Pathogenic

1.1

FATHMM_MKL

Pathogenic

1.0

Vest4

0.99

GERP RS

5.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.90

SpliceAI score (max)

0.34

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.34

Position offset: 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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over