rs863224146

Positions:

• chrX-19358926-C-T

Variant summary

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

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:4
• 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PDHA1	NM_000284.4	c.910C>T	p.Arg304Ter	stop_gained	10/11	ENST00000422285.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PDHA1	ENST00000422285.7	c.910C>T	p.Arg304Ter	stop_gained	10/11	1	NM_000284.4	P1

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:4

Revision: reviewed by expert panel

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 24, 2022	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) -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2024	PDHA1: PVS1, PS2, PM2, PS4:Moderate -

Pyruvate dehydrogenase E1-alpha deficiency Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Génétique des Maladies du Développement, Hospices Civils de Lyon

Oct 22, 2015

- -

Pyruvate dehydrogenase complex deficiency Pathogenic:1

Pathogenic, reviewed by expert panel

curation

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

Apr 02, 2021

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
MutationTaster	Benign	1.0	A;A;A;A;A
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;