rs875989863

Positions:

• chr1-75733587-T-G

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_000016.6(ACADM):​c.346T>G​(p.Cys116Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,812 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C116Y) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: ACADM NM_000016.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:3
• Conservation: PhyloP100: 7.65

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]

ACADM (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000016.6
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-75733588-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 226068.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.975
• PP5: Variant 1-75733587-T-G is Pathogenic according to our data. Variant chr1-75733587-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 226076.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=2, Likely_pathogenic=3}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ACADM	NM_000016.6	c.346T>G	p.Cys116Gly	missense_variant	5/12	ENST00000370841.9	NP_000007.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ACADM	ENST00000370841.9	c.346T>G	p.Cys116Gly	missense_variant	5/12	1	NM_000016.6	ENSP00000359878.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461812 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727206

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.0000227

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Medium-chain acyl-coenzyme A dehydrogenase deficiency Pathogenic:3 Uncertain:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	May 30, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Feb 20, 2015	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 07, 2024	- -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 03, 2024	This sequence change replaces cysteine, which is neutral and slightly polar, with glycine, which is neutral and non-polar, at codon 116 of the ACADM protein (p.Cys116Gly). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with medium-chain acyl-coenzyme A dehydrogenase deficiency (PMID: 20434380). ClinVar contains an entry for this variant (Variation ID: 226076). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt ACADM protein function with a positive predictive value of 80%. Studies have shown that this missense change is associated with inconclusive levels of altered splicing (PMID: 34923709). This variant disrupts the p.Cys116 amino acid residue in ACADM. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 9158144, 19649258, 20567907, 29285339). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Jan 18, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.79	D;D;D;.
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D
M_CAP	Pathogenic	0.81	D
MetaRNN	Pathogenic	0.98	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.1	.;M;.;.
PrimateAI	Benign	0.47	T
PROVEAN	Pathogenic	-11	D;D;D;D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0070	D;D;D;D
Sift4G	Uncertain	0.023	D;D;D;D
Polyphen		1.0	D;D;D;D
Vest4		0.93
MutPred		0.72		.;.;Gain of disorder (P = 0.0438);.;
MVP		0.97
MPC		0.83
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.98
gMVP		0.91

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs875989863; hg19: chr1-76199272;