rs372480044

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BP4_StrongBP6BS1

The NM_004168.4(SDHA):​c.1919A>G​(p.Glu640Gly) variant causes a missense change. The variant allele was found at a frequency of 0.0000769 in 1,613,294 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign 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. E640Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00051 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000031 ( 1 hom. )

Consequence

SDHA
NM_004168.4 missense

Scores

2
4
13

Clinical Significance

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

Conservation

PhyloP100: 5.64

Publications

2 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: Benign. The variant received -9 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.06469253).
BP6
Variant 5-256344-A-G is Benign according to our data. Variant chr5-256344-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 252908.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000512 (78/152216) while in subpopulation AFR AF = 0.00174 (72/41444). AF 95% confidence interval is 0.00141. There are 0 homozygotes in GnomAd4. There are 34 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHANM_004168.4 linkc.1919A>G p.Glu640Gly 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.1919A>G p.Glu640Gly missense_variant Exon 15 of 15 1 NM_004168.4 ENSP00000264932.6 P31040-1
ENSG00000286001ENST00000651543.1 linkn.*652A>G non_coding_transcript_exon_variant Exon 14 of 24 ENSP00000499215.1 A0A494C1T6
ENSG00000286001ENST00000651543.1 linkn.*652A>G 3_prime_UTR_variant Exon 14 of 24 ENSP00000499215.1 A0A494C1T6

Frequencies

GnomAD3 genomes
AF:
0.000512
AC:
78
AN:
152216
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00174
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000107
AC:
27
AN:
251168
AF XY:
0.0000810
show subpopulations
Gnomad AFR exome
AF:
0.00160
Gnomad AMR exome
AF:
0.0000289
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
AF:
0.0000315
AC:
46
AN:
1461078
Hom.:
1
Cov.:
31
AF XY:
0.0000248
AC XY:
18
AN XY:
726912
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00108
AC:
36
AN:
33396
American (AMR)
AF:
0.0000671
AC:
3
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86234
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111372
Other (OTH)
AF:
0.000116
AC:
7
AN:
60356
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.356
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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:
0.000512
AC:
78
AN:
152216
Hom.:
0
Cov.:
33
AF XY:
0.000457
AC XY:
34
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.00174
AC:
72
AN:
41444
American (AMR)
AF:
0.000131
AC:
2
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
4
8
11
15
19
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:
0.000232
Hom.:
0
Bravo
AF:
0.000642
ESP6500AA
AF:
0.000681
AC:
3
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000189
AC:
23

ClinVar

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

Submissions by phenotype

Pheochromocytoma/paraganglioma syndrome 5 Uncertain:2
Apr 21, 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. -

Apr 17, 2018
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. -

Hereditary cancer-predisposing syndrome Uncertain:2
May 06, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.E640G variant (also known as c.1919A>G), located in coding exon 15 of the SDHA gene, results from an A to G substitution at nucleotide position 1919. The glutamic acid at codon 640 is replaced by glycine, an amino acid with similar properties. This alteration was detected in a large Brazilian family with multiple cases of papillary thyroid cancer, but it did not segregate with disease (Accordi ED et al. Eur Thyroid J. 2016 Jul;5:94-9). This amino acid position is well 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. -

Sep 25, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Leigh syndrome;C3150898:Dilated cardiomyopathy 1GG;C3279992:Pheochromocytoma/paraganglioma syndrome 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Uncertain:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Nov 26, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SDHA c.1919A>G (p.Glu640Gly) results in a non-conservative amino acid change located in the Fumarate reductase/succinate dehydrogenase flavoprotein-like, C-terminal domain (IPR015939) of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00011 in 251168 control chromosomes, predominantly at a frequency of 0.0016 within the African or African-American subpopulation in the gnomAD database, including 1 homozygotes. The observed variant frequency within African or African-American control individuals in the gnomAD database exceeds the estimated maximal expected allele frequency for a pathogenic variant in SDHA causing Neurodegeneration With Ataxia And Late-Onset Optic Atrophy phenotype. c.1919A>G has been reported in the literature in a family affected with Familiar Papillary Thyroid Carcinoma but did not segregate with disease (Accordi_2016). These report(s) do not provide unequivocal conclusions about association of the variant with Neurodegeneration With Ataxia And Late-Onset Optic Atrophy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 27493882). ClinVar contains an entry for this variant (Variation ID: 252908). Based on the evidence outlined above, the variant was classified as likely benign. -

Pheochromocytoma/paraganglioma syndrome 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:1
Dec 20, 2019
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 17376234, 27493882, 31376648) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.099
BayesDel_addAF
Benign
-0.28
T
BayesDel_noAF
Benign
-0.19
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Benign
0.33
T;T;.;.
Eigen
Benign
0.053
Eigen_PC
Benign
0.074
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.93
D;D;D;D
M_CAP
Pathogenic
0.35
D
MetaRNN
Benign
0.065
T;T;T;T
MetaSVM
Uncertain
-0.081
T
MutationAssessor
Benign
1.2
.;L;.;.
PhyloP100
5.6
PrimateAI
Benign
0.36
T
PROVEAN
Benign
-1.9
.;N;N;N
REVEL
Uncertain
0.35
Sift
Benign
0.23
.;T;T;T
Sift4G
Benign
0.24
T;T;T;T
Polyphen
0.0020, 0.46
.;B;P;.
Vest4
0.27
MVP
0.81
MPC
0.57
ClinPred
0.083
T
GERP RS
4.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.28
gMVP
0.73
Mutation Taster
=93/7
polymorphism

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: rs372480044; hg19: chr5-256459; COSMIC: COSV53765192; COSMIC: COSV53765192; API