rs146990772

Positions:

• chr5-236597-C-A
• chr5-236597-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_004168.4(SDHA):​c.1430C>A​(p.Pro477His) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SDHA NM_004168.4 missense, splice_region
• Scores: Splicing: ADA: 0.9235
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.58

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SDHA	NM_004168.4	c.1430C>A	p.Pro477His	missense_variant, splice_region_variant	10/15	ENST00000264932.11	NP_004159.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SDHA	ENST00000264932.11	c.1430C>A	p.Pro477His	missense_variant, splice_region_variant	10/15	1	NM_004168.4	ENSP00000264932	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1461510 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727068

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Paragangliomas 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 10, 2020

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 do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with SDHA-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces proline with histidine at codon 477 of the SDHA protein (p.Pro477His). The proline residue is highly conserved and there is a moderate physicochemical difference between proline and histidine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.61
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.010
CADD	Uncertain	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.39	T;T;.;.
Eigen	Uncertain	0.62
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D;D;D;D
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.68	D;D;D;D
MetaSVM	Uncertain	0.098	D
MutationAssessor	Uncertain	2.7	.;M;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.64	T
PROVEAN	Pathogenic	-7.3	.;D;D;D
REVEL	Uncertain	0.43
Sift	Pathogenic	0.0	.;D;D;D
Sift4G	Uncertain	0.044	D;D;D;T
Polyphen		0.089, 1.0	.;B;D;.
Vest4		0.69
MutPred		0.35		.;Loss of ubiquitination at K480 (P = 0.0665);Loss of ubiquitination at K480 (P = 0.0665);.;
MVP		0.86
MPC		1.1
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.83
gMVP		0.61

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.92
dbscSNV1_RF	Benign	0.71
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: rs146990772; hg19: chr5-236712;