rs587781720

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PP3_StrongPP5

The NM_004168.4(SDHA):​c.818C>T​(p.Thr273Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000744 in 1,613,930 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T273A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

SDHA
NM_004168.4 missense

Scores

12
4
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:5

Conservation

PhyloP100: 7.24

Publications

10 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.945
PP5
Variant 5-230923-C-T is Pathogenic according to our data. Variant chr5-230923-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 141401.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHANM_004168.4 linkc.818C>T p.Thr273Ile missense_variant Exon 7 of 15 ENST00000264932.11 NP_004159.2 P31040-1A0A024QZ30

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SDHAENST00000264932.11 linkc.818C>T p.Thr273Ile missense_variant Exon 7 of 15 1 NM_004168.4 ENSP00000264932.6 P31040-1
ENSG00000286001ENST00000651543.1 linkn.818C>T non_coding_transcript_exon_variant Exon 7 of 24 ENSP00000499215.1 A0A494C1T6

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152160
Hom.:
0
Cov.:
33
show subpopulations
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251326
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461770
Hom.:
0
Cov.:
57
AF XY:
0.00000275
AC XY:
2
AN XY:
727196
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.0000447
AC:
2
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111938
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.460
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152160
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74336
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41452
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.000133
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:3Uncertain:5
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Pheochromocytoma/paraganglioma syndrome 5 Uncertain:2
Feb 18, 2016
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Apr 24, 2023
Myriad Genetics, Inc.
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -

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 threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 273 of the SDHA protein (p.Thr273Ile). This variant is present in population databases (rs587781720, gnomAD 0.003%). This missense change has been observed in individuals with gastrointestinal stromal tumor, pheochromocytoma and paraganglioma (PMID: 23109135, 27011036; external communication, internal data). ClinVar contains an entry for this variant (Variation ID: 141401). 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. -

Neoplasm of brain Pathogenic:1
-
Laboratory of Medical Genetics Unit, Bambino Gesù Children's Hospital
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change, c.818C>T, in exon 7 of SDHA gene results in the missense change, p.Thr273Ile. This variant is present in population databases (rs587781720, gnomAD 0.003%). This change has been observed in individuals with GIST (PMID: 23109135, 27011036). ClinVar contains an entry for this variant (Variation ID: 141401). c paraganglioma tumor, diagnosed in a 57-year-old male. This amino acid position is highly conserved in available vertebrate species. In addition, this change is predicted to be deleterious by in silico analysis. For these reasons, this variant has been classified as Likely Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1
Jul 04, 2024
Ambry Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.T273I variant (also known as c.818C>T), located in coding exon 7 of the SDHA gene, results from a C to T substitution at nucleotide position 818. The threonine at codon 273 is replaced by isoleucine, an amino acid with similar properties. This alteration has been previously identified as a somatic finding in several gastrointestinal stromal tumors (GISTs) demonstrating absence of SDHB and presence of SDHA protein staining by IHC (Belinsky MG et al. Genes Chromosomes Cancer. 2013 Feb;52:214-24; Miettinen M et al. Am. J. Surg. Pathol. 2013 Feb;37:234-40; Boikos SA et al. JAMA Oncol. 2016 Jul;2:922-8). Two of these individuals diagnosed with GIST were also found to carry this alteration in germline DNA (Belinsky MG et al. Genes Chromosomes Cancer. 2013 Feb;52:214-24; Boikos SA et al. JAMA Oncol. 2016 Jul;2:922-8), while no germline specimen was available for the third case (Miettinen M et al. Am. J. Surg. Pathol. 2013 Feb;37:234-40). 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. -

not specified Uncertain:1
Feb 17, 2020
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

DNA sequence analysis of the SDHA gene demonstrated a sequence change, c.818C>T, in exon 7 that results in an amino acid change, p.Thr273Ile. This sequence change has been described in the gnomAD database in three individuals (dbSNPrs587781720). The p.Thr273Ile change has been reported in an individual with gastrointestinal stromal tumor (PMID: 23109135). The p.Thr273Ile change affects a highly conserved amino acid residue located in a domain of the SDHA protein that is known to be functional. The p.Thr273Ile substitution appears to be deleterious using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL). Due to the lack of functional studies, the clinical significance of the p.Thr273Ile change remains unknown at this time. -

Dilated cardiomyopathy 1GG;C5543254:Neurodegeneration with ataxia and late-onset optic atrophy;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Uncertain:1
Aug 25, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

not provided Uncertain:1
Aug 18, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 28748451, 23730622, 25394176, 23282968, 24886695, 27986441, 23109135, 36980917, 32741965, 27011036) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.36
D
BayesDel_noAF
Pathogenic
0.36
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Benign
0.40
T;D;.;.
Eigen
Pathogenic
0.83
Eigen_PC
Pathogenic
0.70
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.52
T;D;D;D
M_CAP
Uncertain
0.15
D
MetaRNN
Pathogenic
0.94
D;D;D;D
MetaSVM
Uncertain
0.64
D
MutationAssessor
Pathogenic
3.6
.;H;.;.
PhyloP100
7.2
PrimateAI
Pathogenic
0.83
D
PROVEAN
Pathogenic
-5.5
.;D;D;D
REVEL
Pathogenic
0.83
Sift
Pathogenic
0.0
.;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D
Polyphen
1.0, 1.0
.;D;D;.
Vest4
0.99
MutPred
0.72
.;Loss of phosphorylation at T273 (P = 0.0187);Loss of phosphorylation at T273 (P = 0.0187);.;
MVP
0.93
MPC
1.4
ClinPred
1.0
D
GERP RS
5.0
Varity_R
0.96
gMVP
0.97
Mutation Taster
=4/96
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs587781720; hg19: chr5-231038; COSMIC: COSV53768649; API