rs875989860

Variant names:

• chr1-75762716-CAA-C
• rs875989860
• NM_000016.6:c.1221_1222delAA

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_000016.6(ACADM):​c.1221_1222delAA​(p.Arg408ThrfsTer6) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,607,496 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. Q407Q) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: ACADM NM_000016.6 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 8.04

Genes affected

ACADM (HGNC:89): (acyl-CoA dehydrogenase medium chain) This gene encodes the medium-chain specific (C4 to C12 straight chain) acyl-Coenzyme A dehydrogenase. The homotetramer enzyme catalyzes the initial step of the mitochondrial fatty acid beta-oxidation pathway. Defects in this gene cause medium-chain acyl-CoA dehydrogenase deficiency, a disease characterized by hepatic dysfunction, fasting hypoglycemia, and encephalopathy, which can result in infantile death. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 6 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-75762716-CAA-C is Pathogenic according to our data. Variant chr1-75762716-CAA-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 226069.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
ACADM	NM_000016.6	c.1221_1222delAA	p.Arg408ThrfsTer6	frameshift_variant	Exon 12 of 12	ENST00000370841.9	NP_000007.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ACADM	ENST00000370841.9	c.1221_1222delAA	p.Arg408ThrfsTer6	frameshift_variant	Exon 12 of 12	1	NM_000016.6	ENSP00000359878.5

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151970 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000242

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000117 AC: 17 AN: 1455526 Hom.: 0 AF XY: 0.0000166 AC XY: 12 AN XY: 724468

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: 0.0000154

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151970 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74218

Gnomad4 AFR AF: 0.0000242

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000151

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Medium-chain acyl-coenzyme A dehydrogenase deficiency Pathogenic:4

Sep 06, 2018

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Oct 31, 2024

Department of Genetics, Suzhou Beikang Medical Laboratory

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The c.1221_1222del pathogenic mutation, located in the last exon of the ACADM gene, results the last 14 amino acids are replaced with 5 different amino acids, causing a translational frameshift with a predicted alternate stop codon (p.Arg408Thrfs*6). This mutation has been identified in individual(s) with MCAD deficiency (PMID: 20434380). ClinVar contains an entry for this variant (Variation ID: 226069). This variant is not present in population databases (gnomAD no frequency). For these reasons, this variant has been classified as Likely Pathogenic. -

Feb 20, 2015

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 17, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 226069). For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Ile416 amino acid residue in ACADM. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 20434380, 23430840, 26947917). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. This premature translational stop signal has been observed in individual(s) with MCAD deficiency (PMID: 20434380). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Arg408Thrfs*6) in the ACADM gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 14 amino acid(s) of the ACADM protein. -

not provided Pathogenic:1

Feb 01, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Frameshift variant predicted to result in protein truncation, as the last 14 amino acids are replaced with 5 different amino acids, and other loss-of-function variants have been reported downstream in HGMD; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 20434380, 32778825) -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs875989860; hg19: chr1-76228401;