rs1455783076

chr1-161356838-T-Achr1-161356838-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_003001.5(SDHC):c.403T>A(p.Leu135Met) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,738 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. L135F) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SDHC NM_003001.5 missense, splice_region
• Scores: Splicing: ADA: 0.009837
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.34

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a transmembrane_region Helical (size 24) in uniprot entity C560_HUMAN there are 9 pathogenic changes around while only 1 benign (90%) in NM_003001.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.938

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SDHC	NM_003001.5	c.403T>A	p.Leu135Met	missense_variant, splice_region_variant	5/6	ENST00000367975.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SDHC	ENST00000367975.7	c.403T>A	p.Leu135Met	missense_variant, splice_region_variant	5/6	1	NM_003001.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000402 AC: 1 AN: 249048 Hom.: 0 AF XY: 0.00000742 AC XY: 1 AN XY: 134818

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 SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461738 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727174

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gastrointestinal stromal tumor;C1854336:Paragangliomas 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 12, 2022

This variant is present in population databases (no rsID available, gnomAD 0.003%). 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 534378). This variant has not been reported in the literature in individuals affected with SDHC-related conditions. This sequence change replaces leucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 135 of the SDHC protein (p.Leu135Met). -

Gastrointestinal stromal tumor Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Oct 30, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.27
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.30
Cadd	Uncertain	23
Dann	Uncertain	1.0
DEOGEN2	Benign	0.37	T;.;.
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Benign	0.71	D
LIST_S2	Uncertain	0.89	D;D;D
M_CAP	Pathogenic	0.77	D
MetaRNN	Pathogenic	0.94	D;D;D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Pathogenic	3.5	H;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.52	T
PROVEAN	Benign	-1.6	N;N;N
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	D;D;T
Sift4G	Uncertain	0.040	D;D;D
Polyphen		0.99	D;D;D
Vest4		0.76
MutPred		0.74		Loss of catalytic residue at L135 (P = 0.0037);.;.;
MVP		0.93
MPC		1.1
ClinPred		0.97	D
GERP RS		2.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.93
gMVP		0.74

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0098
dbscSNV1_RF	Benign	0.20
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: rs1455783076; hg19: chr1-161326628;