X-19343959-C-T

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_Strong BS1_Supporting BS2

The NM_000284.4(PDHA1):c.-79C>T variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000219 in 935,380 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 78 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00024 (0 hom., 11 hem., cov: 24)
  • Exomes 𝑓: 0.00022 (0 hom. 67 hem.)
• Consequence: PDHA1 NM_000284.4 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.189

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 Benign. Variant got -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.7).
• BS1: Variant frequency is greater than expected in population mid. gnomad4_exome allele frequency = 0.000216 (178/822632) while in subpopulation MID AF= 0.0012 (3/2499). AF 95% confidence interval is 0.000327. There are 0 homozygotes in gnomad4_exome. There are 67 alleles in male gnomad4_exome subpopulation. Median coverage is 14. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High Hemizygotes in GnomAd at 11 XL gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PDHA1	NM_000284.4	c.-79C>T		5_prime_UTR_variant	1/11	ENST00000422285.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PDHA1	ENST00000422285.7	c.-79C>T		5_prime_UTR_variant	1/11	1	NM_000284.4	P1

Frequencies

GnomAD3 genomes AF: 0.000239 AC: 27 AN: 112748 Hom.: 0 Cov.: 24 AF XY: 0.000315 AC XY: 11 AN XY: 34900

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00867

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000752

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000216 AC: 178 AN: 822632 Hom.: 0 Cov.: 14 AF XY: 0.000287 AC XY: 67 AN XY: 233574

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00733

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000501

Gnomad4 OTH exome AF: 0.000487

GnomAD4 genome AF: 0.000239 AC: 27 AN: 112748 Hom.: 0 Cov.: 24 AF XY: 0.000315 AC XY: 11 AN XY: 34900

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00867

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000752

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000356 Hom.: 1

Bravo AF: 0.000253

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pyruvate dehydrogenase E1-alpha deficiency Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.70
Cadd	Benign	12
Dann	Benign	0.90
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2

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: rs942040058; hg19: chrX-19362077;