rs1060501393

Positions:

• chr1-161340644-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_003001.5(SDHC):​c.230C>A​(p.Ala77Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SDHC NM_003001.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.05

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 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 14 uncertain in NM_003001.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.977

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SDHC	NM_003001.5	c.230C>A	p.Ala77Asp	missense_variant	4/6	ENST00000367975.7	NP_002992.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SDHC	ENST00000367975.7	c.230C>A	p.Ala77Asp	missense_variant	4/6	1	NM_003001.5	ENSP00000356953.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Gastrointestinal stromal tumor;C1854336:Paragangliomas 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 29, 2020

Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with an SDHC-related disease. This sequence change replaces alanine with aspartic acid at codon 77 of the SDHC protein (p.Ala77Asp). The alanine residue is moderately conserved and there is a moderate physicochemical difference between alanine and aspartic acid. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.39
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.61	D;.;.;.;.
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Uncertain	0.96	D;D;D;D;D
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Pathogenic	0.91	D
MutationAssessor	Pathogenic	4.1	H;H;.;.;.
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-3.4	D;D;D;D;D
REVEL	Pathogenic	0.88
Sift	Uncertain	0.012	D;D;D;D;D
Sift4G	Uncertain	0.019	D;D;D;D;D
Polyphen		0.99	D;D;D;D;D
Vest4		0.94
MutPred		0.85		Loss of methylation at R72 (P = 0.0645);Loss of methylation at R72 (P = 0.0645);.;.;.;
MVP		0.97
MPC		1.4
ClinPred		1.0	D
GERP RS		3.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.90
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

Other links and lift over

dbSNP: rs1060501393; hg19: chr1-161310434;