5-225560-G-T

Variant names:

• chr5-225560-G-T
• rs778737664
• NM_004168.4:c.454G>T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_004168.4(SDHA):​c.454G>T​(p.Glu152*) variant causes a stop gained, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,636 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SDHA NM_004168.4 stop_gained, splice_region
• Scores: Splicing: ADA: 0.9823
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.34

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]

ENSG00000286001 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-225560-G-T is Pathogenic according to our data. Variant chr5-225560-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 1071454.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SDHA	NM_004168.4	c.454G>T	p.Glu152*	stop_gained, splice_region_variant	Exon 4 of 15	ENST00000264932.11	NP_004159.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SDHA	ENST00000264932.11	c.454G>T	p.Glu152*	stop_gained, splice_region_variant	Exon 4 of 15	1	NM_004168.4	ENSP00000264932.6
ENSG00000286001	ENST00000651543.1	n.454G>T		splice_region_variant, non_coding_transcript_exon_variant	Exon 4 of 24			ENSP00000499215.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000800 AC: 2 AN: 250048 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135492

Gnomad AFR exome AF: 0.000126

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461636 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727124

Gnomad4 AFR exome AF: 0.0000598

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Jan 23, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Glu152*) in the SDHA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SDHA are known to be pathogenic (PMID: 22974104, 24781757). This variant is present in population databases (no rsID available, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with SDHA-related conditions. ClinVar contains an entry for this variant (Variation ID: 1071454). For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Apr 13, 2021

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.E152* pathogenic mutation (also known as c.454G>T), located in coding exon 4 of the SDHA gene, results from a G to T substitution at nucleotide position 454. This changes the amino acid from a glutamic acid to a stop codon within coding exon 4. This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	49
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.98	D
Vest4		0.94
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.9

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Benign	0.68
SpliceAI score (max)		0.070		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: rs778737664; hg19: chr5-225675;