5-218380-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4BP6

The NM_004168.4(SDHA):​c.25C>T​(p.Arg9Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000138 in 1,454,206 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict 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. R9G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)
Exomes 𝑓: 7.7e-7 ( 0 hom. )

Consequence

SDHA
NM_004168.4 missense

Scores

1
4
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1

Conservation

PhyloP100: 0.272

Publications

0 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]
CCDC127 (HGNC:30520): (coiled-coil domain containing 127) Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.39136142).
BP6
Variant 5-218380-C-T is Benign according to our data. Variant chr5-218380-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 952939.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004168.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SDHA
NM_004168.4
MANE Select
c.25C>Tp.Arg9Trp
missense
Exon 1 of 15NP_004159.2
SDHA
NM_001294332.2
c.25C>Tp.Arg9Trp
missense
Exon 1 of 14NP_001281261.1
SDHA
NM_001330758.2
c.25C>Tp.Arg9Trp
missense
Exon 1 of 13NP_001317687.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SDHA
ENST00000264932.11
TSL:1 MANE Select
c.25C>Tp.Arg9Trp
missense
Exon 1 of 15ENSP00000264932.6
ENSG00000286001
ENST00000651543.1
n.25C>T
non_coding_transcript_exon
Exon 1 of 24ENSP00000499215.1
SDHA
ENST00000510361.5
TSL:2
c.25C>Tp.Arg9Trp
missense
Exon 1 of 14ENSP00000427703.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152172
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000900
AC:
1
AN:
111102
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000146
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
7.68e-7
AC:
1
AN:
1302034
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
642804
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
26812
American (AMR)
AF:
0.00
AC:
0
AN:
24952
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
20206
East Asian (EAS)
AF:
0.0000323
AC:
1
AN:
30984
South Asian (SAS)
AF:
0.00
AC:
0
AN:
64812
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
33642
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
3656
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1043708
Other (OTH)
AF:
0.00
AC:
0
AN:
53262
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00000657
AC:
1
AN:
152172
Hom.:
0
Cov.:
34
AF XY:
0.0000135
AC XY:
1
AN XY:
74342
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41442
American (AMR)
AF:
0.0000654
AC:
1
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000897
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Pheochromocytoma/paraganglioma syndrome 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Uncertain:1
Apr 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
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 9 of the SDHA protein (p.Arg9Trp). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with SDHA-related conditions. ClinVar contains an entry for this variant (Variation ID: 952939). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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.

Hereditary cancer-predisposing syndrome Benign:1
Jun 16, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.35
BayesDel_addAF
Benign
-0.098
T
BayesDel_noAF
Benign
-0.38
CADD
Benign
16
DANN
Benign
0.91
DEOGEN2
Benign
0.30
T
Eigen
Benign
-1.0
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.11
N
LIST_S2
Benign
0.82
T
M_CAP
Pathogenic
0.65
D
MetaRNN
Benign
0.39
T
MetaSVM
Benign
-0.83
T
MutationAssessor
Benign
0.55
N
PhyloP100
0.27
PrimateAI
Uncertain
0.74
T
PROVEAN
Benign
-1.1
N
REVEL
Benign
0.10
Sift
Uncertain
0.0050
D
Sift4G
Uncertain
0.021
D
Polyphen
0.0
B
Vest4
0.41
MutPred
0.72
Loss of disorder (P = 0.0075)
MVP
0.39
MPC
1.3
ClinPred
0.39
T
GERP RS
1.8
PromoterAI
0.099
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.9
Varity_R
0.061
gMVP
0.85
Mutation Taster
=81/19
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: rs776218604; hg19: chr5-218495; API