rs1553997377

Variant names:

• chr5-224493-C-G
• rs1553997377
• NM_004168.4:c.284C>G

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM1 PM2 PP3_Moderate PP5_Very_Strong

The NM_004168.4(SDHA):​c.284C>G​(p.Pro95Arg) 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. P95A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: SDHA NM_004168.4 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.50
• Publications: 0 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: Pathogenic. The variant received 14 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 33 uncertain in NM_004168.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.926
• PP5: Variant 5-224493-C-G is Pathogenic according to our data. Variant chr5-224493-C-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 472381.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHA	NM_004168.4	c.284C>G	p.Pro95Arg	missense_variant	Exon 3 of 15	ENST00000264932.11	NP_004159.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SDHA	ENST00000264932.11	c.284C>G	p.Pro95Arg	missense_variant	Exon 3 of 15	1	NM_004168.4	ENSP00000264932.6
ENSG00000286001	ENST00000651543.1	n.284C>G		non_coding_transcript_exon_variant	Exon 3 of 24			ENSP00000499215.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Sep 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 95 of the SDHA protein (p.Pro95Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with gastrointestinal stromal tumor and/or paraganglioma (external communication, internal data). ClinVar contains an entry for this variant (Variation ID: 472381). 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. 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

Mar 26, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.P95R variant (also known as c.284C>G), located in coding exon 3 of the SDHA gene, results from a C to G substitution at nucleotide position 284. The proline at codon 95 is replaced by arginine, an amino acid with dissimilar properties. The variant has been detected in multiple individuals with SDHA-associated tumors (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	1.0
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Benign	0.41	T;T;.;.
Eigen	Pathogenic	0.76
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Uncertain	0.17	D
MetaRNN	Pathogenic	0.93	D;D;D;D
MetaSVM	Uncertain	0.15	D
MutationAssessor	Uncertain	2.4	.;M;.;M
PhyloP100		7.5
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-8.0	.;D;D;D
REVEL	Pathogenic	0.81
Sift	Pathogenic	0.0	.;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	.;D;D;.
Vest4		0.87
MutPred		0.79		Gain of MoRF binding (P = 0.0065);Gain of MoRF binding (P = 0.0065);Gain of MoRF binding (P = 0.0065);Gain of MoRF binding (P = 0.0065);
MVP		0.90
MPC		1.4
ClinPred		1.0	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.97
gMVP		0.92
Mutation Taster		=13/87	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: rs1553997377; hg19: chr5-224608;