17-7224245-T-C

Variant summary

Our verdict is Pathogenic. Variant got 19 ACMG points: 19P and 0B. PVS1 PM2 PP3 PP5_Very_Strong

The NM_000018.4(ACADVL):c.1532+2T>C variant causes a splice donor change. The variant allele was found at a frequency of 0.00000342 in 1,461,518 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: ACADVL NM_000018.4 splice_donor
• Scores: Splicing: ADA: 0.9994
• Clinical Significance: Likely pathogenic reviewed by expert panel P:4
• Conservation: PhyloP100: 3.96

Genes affected

ACADVL (HGNC:92): (acyl-CoA dehydrogenase very long chain) The protein encoded by this gene is targeted to the inner mitochondrial membrane where it catalyzes the first step of the mitochondrial fatty acid beta-oxidation pathway. This acyl-Coenzyme A dehydrogenase is specific to long-chain and very-long-chain fatty acids. A deficiency in this gene product reduces myocardial fatty acid beta-oxidation and is associated with cardiomyopathy. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 19 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-7224245-T-C is Pathogenic according to our data. Variant chr17-7224245-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 370770.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ACADVL	NM_000018.4	c.1532+2T>C		splice_donor_variant		ENST00000356839.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ACADVL	ENST00000356839.10	c.1532+2T>C		splice_donor_variant		1	NM_000018.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250924 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135676

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

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: 0.00000342 AC: 5 AN: 1461518 Hom.: 0 Cov.: 33 AF XY: 0.00000413 AC XY: 3 AN XY: 727072

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:4

Revision: reviewed by expert panel

Submissions by phenotype

Very long chain acyl-CoA dehydrogenase deficiency Pathogenic:4

Likely pathogenic, reviewed by expert panel	curation	ClinGen ACADVL Variant Curation Expert Panel, ClinGen	Dec 14, 2022	The c.1532+2T>C variant in ACADVL occurs within the canonical splice donor/acceptor site (+/- 1,2) of intron 15. It is predicted to cause skipping of biologically-relevant-exon 15/20, resulting in a frameshift leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1; PMIDs 9973285, 11590124). At least one individual with this variant was identified by newborn screen, but this information is insufficient to use toward classification (PMID: 26385305). The highest population minor allele frequency in gnomAD v2.1 is 0.00005440 in the East Asian population, which is lower than the ClinGen ACADVL Variant Curation Expert Panel threshold (<0.001) for PM2_Supporting, meeting this criterion (PM2_Supporting). In summary, this variant meets the criteria to be classified as likely pathogenic for autosomal recessive very long chain acyl-CoA dehydrogenase (VLCAD) deficiency based on the ACMG/AMP criteria applied, as specified by the ClinGen ACADVL Variant Curation Expert Panel: PVS1, PM2_Supporting. (ACADVL VCEP specifications version 1; approved November 8, 2021) -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Apr 13, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine	Nov 01, 2019	The NM_000018.3:c.1532+2T>C (NP_000009.1:p.?) [GRCH38: NC_000017.11:g.7224245T>C] variant in ACADVL gene is interpretated to be Pathogenic based on ACMG guidelines (PMID: 25741868). This variant has been reported. This variant meets the following evidence codes reported in the ACMG guidelines: PVS1, PS3 -
Likely pathogenic, criteria provided, single submitter	clinical testing	Invitae	Aug 16, 2023	This sequence change affects a donor splice site in intron 15 of the ACADVL gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in ACADVL are known to be pathogenic (PMID: 9973285, 11590124). This variant is present in population databases (rs111851815, gnomAD 0.006%). Disruption of this splice site has been observed in individual(s) with a positive newborn screening result for ACADVL-related disease (PMID: 26385305). ClinVar contains an entry for this variant (Variation ID: 370770). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Benign	-0.16
Cadd	Pathogenic	27
Dann	Benign	0.93
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.97	D
MutationTaster	Benign	1.0	D;D;D
GERP RS		4.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.90
SpliceAI score (max)		0.58		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.58		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs111851815; hg19: chr17-7127564;