NM_000284.4:c.910C>T

Variant names:

• chrX-19358926-C-T
• rs863224146
• NM_000284.4:c.910C>T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM6_Supporting PM2 PVS1 PP4

This summary comes from the ClinGen Evidence Repository: The c.910C>T; p. R304X variant in the PDHA1 gene is a nonsense mutation resulting in truncation >50bp upstream of the last exon-exon junction in PDHA1 and is predicted to undergo nonsense mediated decay (PVS1). While this mutation occurs in a hotspot domain (aa position R304, phosphorylation loop region), it is predicted to undergo nonsense mediated decay so PM1 was not scored. This variant is absent from population databases (PM2). This variant has been reported once in the literature in an 8-day old patient with neonatal lactic acidosis, microcephaly, hypotonia and psychomotor delay (PMID:21914562). The variant was not seen in patient’s mother, but maternity was not confirmed (PM6_supporting). Blood pyruvate was significantly elevated at 0.84mM with a lactate/pyruvate ratio of 19, which the PDHA1 Curation Expert Panel agreed was supportive of pathogenicity (PP4). In summary, this variant meets criteria to be classified as a pathogenic of PDHA1- related pyruvate dehydrogenase deficiency in an X-linked manner. PDHA1-specific ACMG/AMP criteria applied: (PVS1, PM2, PM6_supporting, PP4). This was reviewed with the PDHA1 expert panel on 2/16/2021 and approved on 03/10/2021. LINK:https://erepo.genome.network/evrepo/ui/classification/CA321113/MONDO:0019169/014

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0 (0 hom. 0 hem.)
  • Failed GnomAD Quality Control
• Consequence: PDHA1 NM_000284.4 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:5
• Conservation: PhyloP100: 3.00

Genes affected

PDHA1 (HGNC:8806): (pyruvate dehydrogenase E1 subunit alpha 1) The pyruvate dehydrogenase (PDH) complex is a nuclear-encoded mitochondrial multienzyme complex that catalyzes the overall conversion of pyruvate to acetyl-CoA and CO(2), and provides the primary link between glycolysis and the tricarboxylic acid (TCA) cycle. The PDH complex is composed of multiple copies of three enzymatic components: pyruvate dehydrogenase (E1), dihydrolipoamide acetyltransferase (E2) and lipoamide dehydrogenase (E3). The E1 enzyme is a heterotetramer of two alpha and two beta subunits. This gene encodes the E1 alpha 1 subunit containing the E1 active site, and plays a key role in the function of the PDH complex. Mutations in this gene are associated with pyruvate dehydrogenase E1-alpha deficiency and X-linked Leigh syndrome. Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Mar 2010]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM6: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PDHA1	NM_000284.4	c.910C>T	p.Arg304*	stop_gained	Exon 10 of 11	ENST00000422285.7	NP_000275.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PDHA1	ENST00000422285.7	c.910C>T	p.Arg304*	stop_gained	Exon 10 of 11	1	NM_000284.4	ENSP00000394382.2

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1059100 Hom.: 0 Cov.: 25 AF XY: 0.00 AC XY: 0 AN XY: 332492

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.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: reviewed by expert panel

Submissions by phenotype

Pyruvate dehydrogenase E1-alpha deficiency Pathogenic:2

Sep 05, 2024

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.Arg304*) in the PDHA1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PDHA1 are known to be pathogenic (PMID: 10679936, 21914562). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with pyruvate dehydrogenase complex deficiency (PMID: 33204598). This variant is also known as c.1024C>T (Arg342*). ClinVar contains an entry for this variant (Variation ID: 214935). For these reasons, this variant has been classified as Pathogenic. -

Oct 22, 2015

Génétique des Maladies du Développement, Hospices Civils de Lyon

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:2

May 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PDHA1: PVS1, PS2, PM2, PS4:Moderate -

Jun 24, 2022

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 30283815, 21914562, 33204598) -

Pyruvate dehydrogenase complex deficiency Pathogenic:1

Apr 02, 2021

ClinGen Mitochondrial Disease Nuclear and Mitochondrial Variant Curation Expert Panel, ClinGen

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The c.910C>T; p. R304X variant in the PDHA1 gene is a nonsense mutation resulting in truncation >50bp upstream of the last exon-exon junction in PDHA1 and is predicted to undergo nonsense mediated decay (PVS1). While this mutation occurs in a hotspot domain (aa position R304, phosphorylation loop region), it is predicted to undergo nonsense mediated decay so PM1 was not scored. This variant is absent from population databases (PM2). This variant has been reported once in the literature in an 8-day old patient with neonatal lactic acidosis, microcephaly, hypotonia and psychomotor delay (PMID: 21914562). The variant was not seen in patient’s mother, but maternity was not confirmed (PM6_supporting). Blood pyruvate was significantly elevated at 0.84mM with a lactate/pyruvate ratio of 19, which the PDHA1 Curation Expert Panel agreed was supportive of pathogenicity (PP4). In summary, this variant meets criteria to be classified as a pathogenic of PDHA1- related pyruvate dehydrogenase deficiency in an X-linked manner. PDHA1-specific ACMG/AMP criteria applied: (PVS1, PM2, PM6_supporting, PP4). This was reviewed with the PDHA1 expert panel on 2/16/2021 and approved on 03/10/2021. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	38
DANN	Uncertain	1.0
FATHMM_MKL	Uncertain	0.87	D
Vest4		0.88
GERP RS		4.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs863224146; hg19: chrX-19377044;