5-225988-C-T

Variant names:

• chr5-225988-C-T
• rs553257776
• NM_004168.4:c.562C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM2 PM5 PP3_Strong PP5

The NM_004168.4(SDHA):​c.562C>T​(p.Arg188Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,298 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R188Q) has been classified as Pathogenic.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SDHA NM_004168.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:1 O:1
• Conservation: PhyloP100: 2.17
• Publications: 17 publications found

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]

SDHA Gene-Disease associations (from GenCC):

• hereditary pheochromocytoma-paraganglioma

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• pheochromocytoma/paraganglioma syndrome 5

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Illumina, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• mitochondrial complex II deficiency, nuclear type 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• neurodegeneration with ataxia and late-onset optic atrophy

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• Leigh syndrome

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics, ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• gastrointestinal stromal tumor

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Leigh syndrome with leukodystrophy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• mitochondrial complex II deficiency

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• dilated cardiomyopathy 1GG

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

ENSG00000286001 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr5-225989-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 450839.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.968
• PP5: Variant 5-225988-C-T is Pathogenic according to our data. Variant chr5-225988-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 472395.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHA	NM_004168.4	c.562C>T	p.Arg188Trp	missense_variant	Exon 5 of 15	ENST00000264932.11	NP_004159.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SDHA	ENST00000264932.11	c.562C>T	p.Arg188Trp	missense_variant	Exon 5 of 15	1	NM_004168.4	ENSP00000264932.6
ENSG00000286001	ENST00000651543.1	n.562C>T		non_coding_transcript_exon_variant	Exon 5 of 24			ENSP00000499215.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152180 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251462 AF XY: 0.00000736

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000479 AC: 7 AN: 1461826 Hom.: 0 Cov.: 33 AF XY: 0.00000550 AC XY: 4 AN XY: 727208

African (AFR) AF: 0.0000299 AC: 1 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5732

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1112002

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152298 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74470

African (AFR) AF: 0.00 AC: 0 AN: 41552

American (AMR) AF: 0.00 AC: 0 AN: 15300

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10610

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Pheochromocytoma/paraganglioma syndrome 5 Pathogenic:1 Uncertain:1

Sep 28, 2023

Myriad Genetics, Inc.

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely pathogenic. This variant has been reported in multiple individuals with clinical features of gene-specific disease [PMID: 33362715, 23282968, 32741965, Myriad internal data]. This variant is expected to disrupt protein structure [Myriad internal data]. -

Apr 10, 2024

Molecular Pathology, Peter Maccallum Cancer Centre

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Pheochromocytoma/paraganglioma syndrome 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Pathogenic:1

Nov 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 188 of the SDHA protein (p.Arg188Trp). This variant is present in population databases (rs553257776, gnomAD 0.004%). This missense change has been observed in individuals with gastrointestinal stromal tumor and/or paragangliomas (PMID: 23282968, 33362715; internal data). ClinVar contains an entry for this variant (Variation ID: 472395). 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) has been performed 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. Experimental studies have shown that this missense change affects SDHA function (PMID: 28724664). This variant disrupts the p.Arg188 amino acid residue in SDHA. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 32741965; external communication). 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. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Feb 09, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R188W variant (also known as c.562C>T), located in coding exon 5 of the SDHA gene, results from a C to T substitution at nucleotide position 562. The arginine at codon 188 is replaced by tryptophan, an amino acid with dissimilar properties. This variant has been reported in individuals with a paraganglioma or gastrointestinal stromal tumor (Miettinen M et al, 2013 Feb;37:234-40; Ma X et al. Front Endocrinol (Lausanne), 2020 Dec;11:574662). Functional studies in yeast demonstrated that this variant impairs SDHA activity (Bannon AE et al. Clin Cancer Res, 2017 Nov;23:6733-6743). 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. -

Neoplasm Other:1

Mar 04, 2025

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Significance: -

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.51	D;.;.
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Pathogenic	1.0	D;D;D
M_CAP	Pathogenic	0.72	D
MetaRNN	Pathogenic	0.97	D;D;D
MetaSVM	Pathogenic	0.84	D
MutationAssessor	Pathogenic	4.5	H;.;.
PhyloP100		2.2
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-7.6	D;D;D
REVEL	Pathogenic	0.80
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.98
MutPred		0.83		Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);.;
MVP		0.95
MPC		1.4
ClinPred		1.0	D
GERP RS		4.4
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.6
Varity_R		0.98
gMVP		0.97
Mutation Taster		=16/84	disease causing

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

Other links and lift over

dbSNP: rs553257776; hg19: chr5-226103; COSMIC: COSV53768186; COSMIC: COSV53768186;