1-75734850-G-T

Variant summary

Our verdict is Pathogenic. Variant got 21 ACMG points: 21P and 0B. PS1_Very_Strong PM1 PM2 PP3 PP5_Very_Strong

The NM_000016.6(ACADM):c.447G>T(p.Met149Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,380 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 Likely pathogenic (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin ClinVar.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: ACADM NM_000016.6 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2 U:1
• Conservation: PhyloP100: 7.91

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 21 ACMG points.

• PS1: Transcript NM_000016.6 (ACADM) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar as 3591
• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000016.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.832
• PP5: Variant 1-75734850-G-T is Pathogenic according to our data. Variant chr1-75734850-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 226059.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ACADM	NM_000016.6	c.447G>T	p.Met149Ile	missense_variant	6/12	ENST00000370841.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ACADM	ENST00000370841.9	c.447G>T	p.Met149Ile	missense_variant	6/12	1	NM_000016.6	P4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251328 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135840

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461380 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726998

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2 Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Medium-chain acyl-coenzyme A dehydrogenase deficiency Pathogenic:2 Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jun 03, 2023	For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Met149 amino acid residue in ACADM. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 1684086, 9158144; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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 not expected to disrupt ACADM protein function. ClinVar contains an entry for this variant (Variation ID: 226059). This missense change has been observed in individuals with MCAD deficiency (PMID: 1684086, 9158144; Invitae). This variant is present in population databases (rs121434277, gnomAD 0.003%). This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 149 of the ACADM protein (p.Met149Ile). -
Likely pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Jul 22, 2019	- -
Uncertain significance, flagged submission	clinical testing	Counsyl	Nov 03, 2017	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.79
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.26
Cadd	Benign	21
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.70	D;D;D;.
Eigen	Uncertain	0.23
Eigen_PC	Uncertain	0.39
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Pathogenic	0.48	D
MetaRNN	Pathogenic	0.83	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.56	T
PROVEAN	Benign	-1.6	N;N;N;N
REVEL	Pathogenic	0.68
Sift	Benign	0.086	T;D;D;D
Sift4G	Benign	0.28	T;T;T;T
Polyphen		0.16	B;B;B;B
Vest4		0.68
MutPred		0.68		.;.;Gain of catalytic residue at L187 (P = 0.0219);.;
MVP		0.94
MPC		0.21
ClinPred		0.65	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.52
gMVP		0.79

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs121434277; hg19: chr1-76200535;