NM_004168.4:c.1936G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_004168.4(SDHA):​c.1936G>A​(p.Asp646Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,613,696 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. D646D) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000015 ( 1 hom. )

Consequence

SDHA
NM_004168.4 missense

Scores

4
8
7

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 9.30

Publications

3 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 1 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.796

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHANM_004168.4 linkc.1936G>A p.Asp646Asn missense_variant Exon 15 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.1936G>A p.Asp646Asn missense_variant Exon 15 of 15 1 NM_004168.4 ENSP00000264932.6 P31040-1
ENSG00000286001ENST00000651543.1 linkn.*669G>A non_coding_transcript_exon_variant Exon 14 of 24 ENSP00000499215.1 A0A494C1T6
ENSG00000286001ENST00000651543.1 linkn.*669G>A 3_prime_UTR_variant Exon 14 of 24 ENSP00000499215.1 A0A494C1T6

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152164
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.0000966
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:
0.0000199
AC:
5
AN:
251182
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000151
AC:
22
AN:
1461532
Hom.:
1
Cov.:
35
AF XY:
0.0000165
AC XY:
12
AN XY:
727106
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33458
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.000116
AC:
10
AN:
86244
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000899
AC:
10
AN:
1111730
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.432
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.0000329
AC:
5
AN:
152164
Hom.:
0
Cov.:
34
AF XY:
0.0000403
AC XY:
3
AN XY:
74352
show subpopulations
African (AFR)
AF:
0.0000966
AC:
4
AN:
41420
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5208
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
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:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.555
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000564
Hom.:
0
Bravo
AF:
0.0000642
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Dilated cardiomyopathy 1GG Uncertain:1
Dec 05, 2023
Baylor Genetics
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 Uncertain:1
Jan 17, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 646 of the SDHA protein (p.Asp646Asn). This variant is present in population databases (rs376986935, gnomAD 0.006%). This missense change has been observed in individual(s) with SDHA-related conditions (PMID: 38127826). ClinVar contains an entry for this variant (Variation ID: 566572). 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) indicates that this missense variant is not expected to disrupt SDHA protein function with a negative predictive value of 95%. 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
Aug 04, 2023
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 does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Hereditary cancer-predisposing syndrome Uncertain:1
May 14, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.D646N variant (also known as c.1936G>A), located in coding exon 15 of the SDHA gene, results from a G to A substitution at nucleotide position 1936. The aspartic acid at codon 646 is replaced by asparagine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated 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
0.58
BayesDel_addAF
Benign
-0.098
T
BayesDel_noAF
Benign
-0.20
CADD
Uncertain
26
DANN
Uncertain
0.99
DEOGEN2
Benign
0.36
T;D;.;.
Eigen
Uncertain
0.35
Eigen_PC
Uncertain
0.30
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D;D;D;D
M_CAP
Uncertain
0.21
D
MetaRNN
Pathogenic
0.80
D;D;D;D
MetaSVM
Uncertain
0.17
D
MutationAssessor
Uncertain
2.6
.;M;.;.
PhyloP100
9.3
PrimateAI
Uncertain
0.68
T
PROVEAN
Benign
-2.2
.;N;N;N
REVEL
Uncertain
0.43
Sift
Benign
0.091
.;T;T;T
Sift4G
Benign
0.42
T;T;T;T
Polyphen
0.33, 1.0
.;B;D;.
Vest4
0.81
MVP
0.84
MPC
0.50
ClinPred
0.57
D
GERP RS
4.1
Varity_R
0.62
gMVP
0.72
Mutation Taster
=19/81
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

Publications

Other links and lift over

dbSNP: rs376986935; hg19: chr5-256476; API