5-228261-G-T

Position:

• chr5-228261-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PP3_Strong

The NM_004168.4(SDHA):​c.698G>T​(p.Gly233Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000411 in 1,461,450 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: SDHA NM_004168.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 9.50

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]

ENSG00000286001 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SDHA	NM_004168.4	c.698G>T	p.Gly233Val	missense_variant	6/15	ENST00000264932.11	NP_004159.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SDHA	ENST00000264932.11	c.698G>T	p.Gly233Val	missense_variant	6/15	1	NM_004168.4	ENSP00000264932.6
ENSG00000286001	ENST00000651543.1	n.698G>T		non_coding_transcript_exon_variant	6/24			ENSP00000499215.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1461450 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727062

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00000450

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 09, 2024

This sequence change replaces glycine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 233 of the SDHA protein (p.Gly233Val). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with SDH-deficient gastrointestinal stromal tumors (PMID: 35059314). ClinVar contains an entry for this variant (Variation ID: 239681). 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 expected to disrupt SDHA protein function with a positive 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Mayo Clinic Laboratories, Mayo Clinic

Feb 21, 2023

PP3, PM3 -

Gastrointestinal stromal tumor Uncertain:1

Uncertain significance, criteria provided, single submitter

research

“Giorgio Prodi” Cancer Research Center, University of Bologna

Oct 01, 2021

- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 05, 2024

The p.G233V variant (also known as c.698G>T), located in coding exon 6 of the SDHA gene, results from a G to T substitution at nucleotide position 698. The glycine at codon 233 is replaced by valine, an amino acid with dissimilar properties. This variant was detected in a patient with a gastric SDHA-mutant GIST (Pantaleo MA et al. Front Oncol, 2021 Jan;11:778461). This variant was also detected in a patient with no personal or family history of SDHA-associated tumors in a cohort of 8600 patients who had tested positive for a SHDx variant regardless of history (Rana HQ et al. Cancers (Basel), 2024 Feb;16). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.66	D;.;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D;D
M_CAP	Pathogenic	0.43	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.5	H;.;.
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-8.6	D;D;D
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.99
MutPred		0.82		Gain of catalytic residue at G233 (P = 0.1366);Gain of catalytic residue at G233 (P = 0.1366);.;
MVP		0.89
MPC		1.6
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.98
gMVP		0.96

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: rs878854636; hg19: chr5-228376;