rs779113356

Variant names:

• chr2-26192342-TA-T
• rs779113356
• NM_000182.5:c.1967delT

Variant summary

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

The NM_000182.5(HADHA):​c.1967delT​(p.Leu656fs) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000138 in 1,452,832 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: HADHA NM_000182.5 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 8.80

Genes affected

HADHA (HGNC:4801): (hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit alpha) This gene encodes the alpha subunit of the mitochondrial trifunctional protein, which catalyzes the last three steps of mitochondrial beta-oxidation of long chain fatty acids. The mitochondrial membrane-bound heterocomplex is composed of four alpha and four beta subunits, with the alpha subunit catalyzing the 3-hydroxyacyl-CoA dehydrogenase and enoyl-CoA hydratase activities. Mutations in this gene result in trifunctional protein deficiency or LCHAD deficiency. The genes of the alpha and beta subunits of the mitochondrial trifunctional protein are located adjacent to each other in the human genome in a head-to-head orientation. [provided by RefSeq, Jul 2008]

GAREM2 (HGNC:27172): (GRB2 associated regulator of MAPK1 subtype 2)

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 2-26192342-TA-T is Pathogenic according to our data. Variant chr2-26192342-TA-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 188712.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
HADHA	NM_000182.5	c.1967delT	p.Leu656fs	frameshift_variant	Exon 18 of 20	ENST00000380649.8	NP_000173.2
GAREM2	XM_011532567.4	c.1683+5031delA		intron_variant	Intron 6 of 6		XP_011530869.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HADHA	ENST00000380649.8	c.1967delT	p.Leu656fs	frameshift_variant	Exon 18 of 20	1	NM_000182.5	ENSP00000370023.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251484 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135916

Gnomad AFR exome AF: 0.00

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1452832 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 723480

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: 0.00000181

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Long chain 3-hydroxyacyl-CoA dehydrogenase deficiency Pathogenic:3

Aug 21, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 04, 2014

Counsyl

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

- -

May 22, 2017

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: The HADHA c.1967delT (p.Leu656X) variant results in a premature termination codon, predicted to cause a truncated or absent HADHA protein due to nonsense mediated decay, which are commonly known mechanisms for disease. One in silico tool predicts a damaging outcome for this variant. This variant was found in 1/121390 control chromosomes at a frequency of 0.0000082, which does not exceed the estimated maximal expected allele frequency of a pathogenic HADHA variant (0.0019365). This variant has been reported in multiple patients as compound heterozygotes (Ibdah_!999 and Boutron_2011). One of patients showed 26% of residual LCHAD activity relative to the controls mean in fibroblasts and 2% of residual LKAT activity relative to the controls mean (Boutron_2011). In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic/likely pathogenic. Taken together, this variant is classified as pathogenic. -

not provided Pathogenic:1

Feb 15, 2025

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Identified with a second HADHA variant in patients with mitochondrial trifunctional protein deficiency in published literature (PMID: 21549624); 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: 22459206, 21103935, Zhu_2020[Case_report], 7738175, 21549624, 10352164) -

Mitochondrial trifunctional protein deficiency;C3711645:Long chain 3-hydroxyacyl-CoA dehydrogenase deficiency Pathogenic:1

Mar 03, 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.Leu656*) in the HADHA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HADHA are known to be pathogenic (PMID: 7738175, 21103935, 21549624, 22459206). This variant is present in population databases (rs779113356, gnomAD 0.0009%). This premature translational stop signal has been observed in individual(s) with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency or deficiency of mitochondrial trifunctional protein (PMID: 10352164, 21549624). This variant is also known as Leu620Ter. ClinVar contains an entry for this variant (Variation ID: 188712). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs779113356; hg19: chr2-26415211;