chr1-161323615-C-A

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_003001.5(SDHC):​c.22C>A​(p.His8Asn) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000149 in 1,612,810 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H8Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

SDHC
NM_003001.5 missense, splice_region

Scores

7
12
Splicing: ADA: 0.0001109
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.03

Publications

1 publications found
Variant links:
Genes affected
SDHC (HGNC:10682): (succinate dehydrogenase complex subunit C) This gene encodes one of four nuclear-encoded subunits that comprise succinate dehydrogenase, also known as mitochondrial complex II, a key enzyme complex of the tricarboxylic acid cycle and aerobic respiratory chains of mitochondria. The encoded protein is one of two integral membrane proteins that anchor other subunits of the complex, which form the catalytic core, to the inner mitochondrial membrane. There are several related pseudogenes for this gene on different chromosomes. Mutations in this gene have been associated with paragangliomas. Alternatively spliced transcript variants have been described. [provided by RefSeq, May 2013]
SDHC Gene-Disease associations (from GenCC):
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • pheochromocytoma/paraganglioma syndrome 3
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • Carney-Stratakis syndrome
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
  • gastrointestinal stromal tumor
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • renal cell carcinoma
    Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
  • Cowden disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • mitochondrial disease
    Inheritance: Unknown Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.18479407).
BS2
High AC in GnomAdExome4 at 23 Unknown,AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SDHCNM_003001.5 linkc.22C>A p.His8Asn missense_variant, splice_region_variant Exon 2 of 6 ENST00000367975.7 NP_002992.1 Q99643-1A0A0S2Z4B7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SDHCENST00000367975.7 linkc.22C>A p.His8Asn missense_variant, splice_region_variant Exon 2 of 6 1 NM_003001.5 ENSP00000356953.3 Q99643-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152186
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000281
AC:
7
AN:
248980
AF XY:
0.0000371
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000157
AC:
23
AN:
1460624
Hom.:
0
Cov.:
30
AF XY:
0.0000234
AC XY:
17
AN XY:
726748
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39682
South Asian (SAS)
AF:
0.000267
AC:
23
AN:
86230
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53388
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1110904
Other (OTH)
AF:
0.00
AC:
0
AN:
60350
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.453
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:
0.00000657
AC:
1
AN:
152186
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74342
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
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

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
ExAC
AF:
0.0000412
AC:
5

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Pheochromocytoma/paraganglioma syndrome 3 Uncertain:1
-
Neuberg Centre For Genomic Medicine, NCGM
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The missense variant p.H8N in SDHC (NM_003001.5) has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The p.His8Asn variant is novel (not in any individuals) in 1000 Genomes. There is a small physicochemical difference between histidine and asparagine, which is not likely to impact secondary protein structure as these residues share similar properties. In silico tools predict the variant to be tolerated. The residue is conserved across species. The amino acid change p.His8Asn in SDHC is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Hereditary cancer-predisposing syndrome Uncertain:1
Jan 04, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.H8N variant (also known as c.22C>A), located in coding exon 2 of the SDHC gene, results from a C to A substitution at nucleotide position 22. The histidine at codon 8 is replaced by asparagine, an amino acid with similar properties. This alteration was identified in 2/1358 non-cancer control individuals and in 0/57 cases, in a study looking at cancer predisposition mutations in patients with cutaneous melanoma and a history of at least two additional non-cutaneous melanoma primary cancers (Pritchard AL et al. PLoS One, 2018 Apr;13:e0194098). This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Gastrointestinal stromal tumor;C1854336:Pheochromocytoma/paraganglioma syndrome 3 Uncertain:1
Sep 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces histidine, which is basic and polar, with asparagine, which is neutral and polar, at codon 8 of the SDHC protein (p.His8Asn). This variant is present in population databases (rs746666691, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with SDHC-related conditions. ClinVar contains an entry for this variant (Variation ID: 1513452). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The asparagine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.085
BayesDel_addAF
Benign
-0.090
T
BayesDel_noAF
Uncertain
-0.070
CADD
Benign
13
DANN
Benign
0.80
DEOGEN2
Benign
0.14
T;.;.;.
Eigen
Benign
-0.28
Eigen_PC
Benign
-0.22
FATHMM_MKL
Uncertain
0.82
D
LIST_S2
Benign
0.65
T;T;T;T
M_CAP
Uncertain
0.15
D
MetaRNN
Benign
0.18
T;T;T;T
MetaSVM
Uncertain
0.54
D
MutationAssessor
Uncertain
2.0
M;M;M;M
PhyloP100
1.0
PrimateAI
Uncertain
0.52
T
PROVEAN
Benign
-0.89
N;N;N;D
REVEL
Uncertain
0.30
Sift
Benign
0.31
T;D;D;D
Sift4G
Benign
0.24
T;D;D;D
Polyphen
0.24
B;D;B;B
Vest4
0.42
MutPred
0.28
Gain of methylation at R7 (P = 0.0887);Gain of methylation at R7 (P = 0.0887);Gain of methylation at R7 (P = 0.0887);Gain of methylation at R7 (P = 0.0887);
MVP
0.93
MPC
0.39
ClinPred
0.037
T
GERP RS
3.3
Varity_R
0.054
gMVP
0.54
Mutation Taster
=81/19
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00011
dbscSNV1_RF
Benign
0.032
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: rs746666691; hg19: chr1-161293405; API