rs1554002483

Variant names:

• chr5-254471-C-T
• rs1554002483
• NM_004168.4:c.1873C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_004168.4(SDHA):​c.1873C>T​(p.His625Tyr) variant causes a missense change. 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H625R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0000021 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SDHA NM_004168.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.04
• Publications: 2 publications found

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]

SDHA Gene-Disease associations (from GenCC):

• hereditary pheochromocytoma-paraganglioma

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• pheochromocytoma/paraganglioma syndrome 5

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Illumina, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• mitochondrial complex II deficiency, nuclear type 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• neurodegeneration with ataxia and late-onset optic atrophy

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• Leigh syndrome

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics, ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• gastrointestinal stromal tumor

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Leigh syndrome with leukodystrophy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• mitochondrial complex II deficiency

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• dilated cardiomyopathy 1GG

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

ENSG00000286001 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.964

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHA	NM_004168.4	c.1873C>T	p.His625Tyr	missense_variant	Exon 14 of 15	ENST00000264932.11	NP_004159.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SDHA	ENST00000264932.11	c.1873C>T	p.His625Tyr	missense_variant	Exon 14 of 15	1	NM_004168.4	ENSP00000264932.6
ENSG00000286001	ENST00000651543.1	n.*606C>T		non_coding_transcript_exon_variant	Exon 13 of 24			ENSP00000499215.1
ENSG00000286001	ENST00000651543.1	n.*606C>T		3_prime_UTR_variant	Exon 13 of 24			ENSP00000499215.1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000210 AC: 3 AN: 1431788 Hom.: 0 Cov.: 32 AF XY: 0.00000282 AC XY: 2 AN XY: 709332

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 32726

American (AMR) AF: 0.00 AC: 0 AN: 40794

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25506

East Asian (EAS) AF: 0.00 AC: 0 AN: 38774

South Asian (SAS) AF: 0.00 AC: 0 AN: 81972

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51490

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4242

European-Non Finnish (NFE) AF: 0.00000273 AC: 3 AN: 1097160

Other (OTH) AF: 0.00 AC: 0 AN: 59124

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 30

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pheochromocytoma/paraganglioma syndrome 5;C5700310:Mitochondrial complex II deficiency, nuclear type 1 Uncertain:1

Mar 07, 2022

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 tyrosine, which is neutral and polar, at codon 625 of the SDHA protein (p.His625Tyr). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with carotid body paraganglioma and pituitary macroadenoma (PMID: 23633203). ClinVar contains an entry for this variant (Variation ID: 472364). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. 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	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.17
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Benign	0.41	T;D;.;.
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.98	D;D;D;D
M_CAP	Pathogenic	0.78	D
MetaRNN	Pathogenic	0.96	D;D;D;D
MetaSVM	Pathogenic	0.87	D
MutationAssessor	Pathogenic	4.4	.;H;.;.
PhyloP100		7.0
PrimateAI	Uncertain	0.75	T
PROVEAN	Pathogenic	-5.1	.;D;D;D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	.;D;T;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0, 0.93	.;D;P;.
Vest4		0.70
MutPred		0.90		.;Gain of helix (P = 0.0325);.;.;
MVP		0.94
MPC		1.5
ClinPred		1.0	D
GERP RS		4.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.94
Mutation Taster		=3/97	disease causing

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

Other links and lift over

dbSNP: rs1554002483; hg19: chr5-254586;