11-112086911-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_003002.4(SDHD):c.4G>A(p.Ala2Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,890 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A2V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SDHD NM_003002.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.01

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.784

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SDHD	NM_003002.4	c.4G>A	p.Ala2Thr	missense_variant	1/4	ENST00000375549.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SDHD	ENST00000375549.8	c.4G>A	p.Ala2Thr	missense_variant	1/4	1	NM_003002.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251428 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135878

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 6.84e-7 AC: 1 AN: 1461890 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 24, 2023

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 2 of the SDHD protein (p.Ala2Thr). This variant is present in population databases (no rsID available, gnomAD 0.003%). 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: 646883). 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 SDHD protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.20
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.25
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Benign	0.39	T;.;.;.;.;.;.
Eigen	Uncertain	0.23
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Benign	0.64	T;T;T;T;T;.;T
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.78	D;D;D;D;D;D;D
MetaSVM	Uncertain	0.48	D
MutationAssessor	Uncertain	2.3	M;M;.;M;.;M;M
MutationTaster	Benign	0.94	D;D;D;D;N
PrimateAI	Uncertain	0.67	T
PROVEAN	Benign	-1.7	N;.;N;D;N;N;N
REVEL	Uncertain	0.55
Sift	Uncertain	0.0080	D;.;D;D;D;D;D
Sift4G	Uncertain	0.029	D;D;D;D;D;D;T
Polyphen		0.89	P;.;.;.;.;.;.
Vest4		0.68
MutPred		0.35		Gain of disorder (P = 0.1563);Gain of disorder (P = 0.1563);Gain of disorder (P = 0.1563);Gain of disorder (P = 0.1563);Gain of disorder (P = 0.1563);Gain of disorder (P = 0.1563);Gain of disorder (P = 0.1563);
MVP		0.97
MPC		0.43
ClinPred		0.97	D
GERP RS		5.2
RBP_binding_hub_radar		0.97
RBP_regulation_power_radar		2.8
Varity_R		0.19
gMVP		0.80

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1401420432; hg19: chr11-111957635;