rs763766162

Positions:

• chr5-251440-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_004168.4(SDHA):​c.1766G>A​(p.Arg589Gln) variant causes a missense 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. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R589W) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SDHA NM_004168.4 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 9.43

Genes affected

SDHA (HGNC:10680): (succinate dehydrogenase complex flavoprotein subunit A) This gene encodes a major catalytic subunit of succinate-ubiquinone oxidoreductase, a complex of the mitochondrial respiratory chain. The complex is composed of four nuclear-encoded subunits and is localized in the mitochondrial inner membrane. Mutations in this gene have been associated with a form of mitochondrial respiratory chain deficiency known as Leigh Syndrome. A pseudogene has been identified on chromosome 3q29. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2014]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 15 uncertain in NM_004168.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr5-251439-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 30132.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988
• PP5: Variant 5-251440-G-A is Pathogenic according to our data. Variant chr5-251440-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 412342.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SDHA	NM_004168.4	c.1766G>A	p.Arg589Gln	missense_variant	13/15	ENST00000264932.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SDHA	ENST00000264932.11	c.1766G>A	p.Arg589Gln	missense_variant	13/15	1	NM_004168.4	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000274 AC: 4 AN: 1461640 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727126

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Paragangliomas 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

Dec 14, 2023

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 589 of the SDHA protein (p.Arg589Gln). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with gastrointestinal stromal tumors and paraganglioma-pheochromocytoma syndromes (PMID: 23612575, 25720320, 28384794). ClinVar contains an entry for this variant (Variation ID: 412342). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on SDHA protein function. This variant disrupts the p.Arg589 amino acid residue in SDHA. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 20484225, 22955521, 25405498, 28546994). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Dilated cardiomyopathy 1GG Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

May 17, 2023

- -

Gastrointestinal stromal tumor Pathogenic:1

Likely pathogenic, criteria provided, single submitter

research

“Giorgio Prodi” Cancer Research Center, University of Bologna

Oct 01, 2021

- -

Hereditary cancer-predisposing syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 18, 2023

The p.R589Q variant (also known as c.1766G>A), located in coding exon 13 of the SDHA gene, results from a G to A substitution at nucleotide position 1766. The arginine at codon 589 is replaced by glutamine, an amino acid with highly similar properties. This variant has been detected in individuals with a history of paraganglioma/pheochromocytoma (Papathomas TG et al. Mod Pathol, 2015 Jun;28:807-21; Bausch B et al. JAMA Oncol, 2017 Sep;3:1204-1212), as well as an individual with a gastrointestinal stromal tumor (GIST) that showed loss of SDHA by immunohistochemistry (IHC) (Pantaleo MA et al. Eur J Hum Genet, 2014 Jan;22:32-9; Pantaleo MA et al. Front Oncol, 2021 Jan;11:778461). Based on internal structural analysis, p.R589Q disrupt the structural stability (Ambry internal data). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). 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 majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.60	D;D;.;D
Eigen	Uncertain	0.62
Eigen_PC	Uncertain	0.36
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Uncertain	0.24	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.76	T
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	.;D;.;.
Vest4		0.97
MutPred		0.95		.;Gain of ubiquitination at K586 (P = 0.0822);.;.;
MVP		0.93
MPC		1.5
ClinPred		1.0	D
GERP RS		3.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.99
gMVP		0.95

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: rs763766162; hg19: chr5-251555; COSMIC: COSV53766603; COSMIC: COSV53766603;