11-112086925-G-T

Variant names:

• chr11-112086925-G-T
• rs200895313
• NM_003002.4:c.18G>T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_003002.4(SDHD):​c.18G>T​(p.Arg6Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SDHD NM_003002.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 1.16

Genes affected

SDHD (HGNC:10683): (succinate dehydrogenase complex subunit D) This gene encodes a member of complex II of the respiratory chain, which is responsible for the oxidation of succinate. The encoded protein is one of two integral membrane proteins anchoring the complex to the matrix side of the mitochondrial inner membrane. Mutations in this gene are associated with the formation of tumors, including hereditary paraganglioma. Transmission of disease occurs almost exclusively through the paternal allele, suggesting that this locus may be maternally imprinted. There are pseudogenes for this gene on chromosomes 1, 2, 3, 7, and 18. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2013]

ENSG00000255292 (HGNC:):

TIMM8B (HGNC:11818): (translocase of inner mitochondrial membrane 8 homolog B) This gene encodes a member of a well-conserved family of proteins with similarity to yeast Tim mitochondrial import proteins. This gene is encoded by a nuclear gene and is transported into the intermembrane space of the mitochondrion. When formed into complexes, these proteins guide membrane-spanning proteins across the mitochondrial intermembrane space before they are added into the mitochondrial inner membrane. This gene is adjacent to succinate dehydrogenase, subunit D (SDHD), in which mutations have been found in affected members of families with hereditary paraganglioma.[provided by RefSeq, Aug 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHD	NM_003002.4	c.18G>T	p.Arg6Ser	missense_variant	Exon 1 of 4	ENST00000375549.8	NP_002993.1
TIMM8B	NM_012459.4	c.-202C>A		upstream_gene_variant		ENST00000504148.3	NP_036591.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SDHD	ENST00000375549.8	c.18G>T	p.Arg6Ser	missense_variant	Exon 1 of 4	1	NM_003002.4	ENSP00000364699.3
ENSG00000255292	ENST00000532699.1	n.18G>T		non_coding_transcript_exon_variant	Exon 1 of 6	3		ENSP00000456434.1
TIMM8B	ENST00000504148.3	c.-202C>A		upstream_gene_variant		1	NM_012459.4	ENSP00000422122.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Pheochromocytoma;C1847319:Carney-Stratakis syndrome;C1868633:Paragangliomas with sensorineural hearing loss;CN166604:Cowden syndrome 3 Uncertain:1

Nov 20, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 6 of the SDHD protein (p.Arg6Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SDHD-related conditions. ClinVar contains an entry for this variant (Variation ID: 581402). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt SDHD protein function with a positive predictive value of 95%. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

May 24, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R6S variant (also known as c.18G>T), located in coding exon 1 of the SDHD gene, results from a G to T substitution at nucleotide position 18. The arginine at codon 6 is replaced by serine, 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. Based on the available evidence, the clinical significance of this variant remains unclear. -

Hereditary pheochromocytoma-paraganglioma Uncertain:1

Dec 01, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces arginine with serine at codon 6 of the SDHD protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.31
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.37
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.39	T;.;.;.;.;.;.
Eigen	Benign	-0.40
Eigen_PC	Benign	-0.38
FATHMM_MKL	Benign	0.58	D
LIST_S2	Benign	0.67	T;T;T;T;T;.;T
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.69	D;D;D;D;D;D;D
MetaSVM	Uncertain	0.23	D
MutationAssessor	Uncertain	2.3	M;M;.;M;.;M;M
PrimateAI	Uncertain	0.51	T
PROVEAN	Benign	-1.9	N;.;N;D;N;N;N
REVEL	Pathogenic	0.65
Sift	Uncertain	0.0030	D;.;D;D;D;D;D
Sift4G	Uncertain	0.016	D;D;D;D;D;D;T
Polyphen		0.68	P;.;.;.;.;.;.
Vest4		0.53
MutPred		0.67		Loss of MoRF binding (P = 2e-04);Loss of MoRF binding (P = 2e-04);Loss of MoRF binding (P = 2e-04);Loss of MoRF binding (P = 2e-04);Loss of MoRF binding (P = 2e-04);Loss of MoRF binding (P = 2e-04);Loss of MoRF binding (P = 2e-04);
MVP		1.0
MPC		0.25
ClinPred		0.91	D
GERP RS		2.2
RBP_binding_hub_radar		0.97
RBP_regulation_power_radar		3.8
Varity_R		0.15
gMVP		0.71

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

Other links and lift over

dbSNP: rs200895313; hg19: chr11-111957649;