rs1332910409

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 6P and 4B. PM1PP3_StrongBS2

The NM_003001.5(SDHC):​c.221C>T​(p.Thr74Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000093 in 1,613,736 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T74A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

SDHC
NM_003001.5 missense

Scores

11
7
1

Clinical Significance

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

Conservation

PhyloP100: 2.04
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 14 uncertain in NM_003001.5
PP3
MetaRNN computational evidence supports a deleterious effect, 0.946
BS2
High AC in GnomAdExome4 at 14 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
SDHCNM_003001.5 linkuse as main transcriptc.221C>T p.Thr74Ile missense_variant 4/6 ENST00000367975.7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
SDHCENST00000367975.7 linkuse as main transcriptc.221C>T p.Thr74Ile missense_variant 4/61 NM_003001.5 P1Q99643-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152168
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000958
AC:
14
AN:
1461568
Hom.:
0
Cov.:
31
AF XY:
0.0000124
AC XY:
9
AN XY:
727114
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000117
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152168
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74334
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756

ClinVar

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

Submissions by phenotype

Gastrointestinal stromal tumor;C1854336:Paragangliomas 3 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingInvitaeNov 19, 2023This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 74 of the SDHC protein (p.Thr74Ile). This variant is not present in population databases (gnomAD no frequency). 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: 465964). 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 expected to disrupt SDHC protein function with a positive predictive value of 80%. 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
Uncertain significance, criteria provided, single submitterclinical testingGeneDxJul 28, 2022Not 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; Has not been previously published as pathogenic or benign to our knowledge -
Hereditary cancer-predisposing syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsAug 03, 2022The c.221C>T (p.T74I) alteration is located in exon 4 (coding exon 4) of the SDHC gene. This alteration results from a C to T substitution at nucleotide position 221, causing the threonine (T) at amino acid position 74 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.94
BayesDel_addAF
Pathogenic
0.35
D
BayesDel_noAF
Pathogenic
0.26
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.72
D;.;.;.;.
Eigen
Pathogenic
0.70
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Uncertain
0.81
D
LIST_S2
Uncertain
0.93
D;D;D;D;D
M_CAP
Uncertain
0.18
D
MetaRNN
Pathogenic
0.95
D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.5
H;H;.;.;.
MutationTaster
Benign
1.0
D;D;D;D;D
PrimateAI
Uncertain
0.56
T
PROVEAN
Pathogenic
-5.3
D;D;D;D;D
REVEL
Pathogenic
0.91
Sift
Uncertain
0.0010
D;D;D;D;D
Sift4G
Pathogenic
0.0010
D;D;D;D;D
Polyphen
1.0
D;D;D;D;D
Vest4
0.77
MutPred
0.85
Loss of methylation at R72 (P = 0.0517);Loss of methylation at R72 (P = 0.0517);.;.;.;
MVP
0.99
MPC
1.1
ClinPred
1.0
D
GERP RS
4.1
Varity_R
0.92
gMVP
0.96

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1332910409; hg19: chr1-161310425; API