Genetic Variant MCEE:p.Lys141GlufsTer7 (chr2-71110081-C-CT) – ACMG Classification: Likely_pathogenic (6 pts)

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_StrongPM2

The NM_032601.4(MCEE):c.419dupA(p.Lys141GlufsTer7) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000931 in 1,611,984 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

MCEE
NM_032601.4 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.23

Variant links:

Genes affected

MCEE (HGNC:16732): (methylmalonyl-CoA epimerase) The product of this gene catalyzes the interconversion of D- and L-methylmalonyl-CoA during the degradation of branched chain amino acids. odd chain-length fatty acids, and other metabolites. Mutations in this gene result in methylmalonyl-CoA epimerase deficiency, which is presented as mild to moderate methylmalonic aciduria. [provided by RefSeq, Jul 2008]

MCEE links:

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ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 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. Fraction of 0.211 CDS is truncated, and there are 0 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MCEE	NM_032601.4 link	c.419dupA	p.Lys141GlufsTer7	frameshift_variant	Exon 3 of 3	ENST00000244217.6	NP_115990.3	Q96PE7
MCEE	XM_005264613.3 link	c.257dupA	p.Lys87GlufsTer7	frameshift_variant	Exon 3 of 3		XP_005264670.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
MCEE	ENST00000244217.6 link	c.419dupA	p.Lys141GlufsTer7	frameshift_variant	Exon 3 of 3	1	NM_032601.4	ENSP00000244217.5	Q96PE7
MCEE	ENST00000413592.5 link	c.125dupA	p.Lys43GlufsTer7	frameshift_variant	Exon 2 of 2	2		ENSP00000391140.1	H7BZS7
MCEE	ENST00000462609.2 link	n.365dupA		non_coding_transcript_exon_variant	Exon 5 of 5	3

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151896

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000959

AC:

AN:

1460088

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

726388

show subpopulations

Gnomad4 AFR exome

AF:

0.0000598

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000810

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000658

AC:

AN:

151896

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74190

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000147

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Apr 11, 2022

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

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: MCEE c.419dupA (p.Lys141GlufsX7) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay. A truncating mutation located in close proximity to the current variant (p.Lys140Argfs*6) has been reported in HGMD in association with Parkinson disease, dementia, stroke and elevated levels of methylmalonic acid. While the current variant may not result in NMD, it alters several amino acids located in the Vicinal oxygen chelate (VOC) domain (Interpro). It is unclear what impact the variant will have on the function of this protein. The variant was absent in 250236 control chromosomes. To our knowledge, no occurrence of c.419dupA in individuals affected with Methylmalonic Acidemia and no experimental evidence demonstrating its impact on protein function have been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as VUS - possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

Below is the list of publications found by LitVar. It may be empty.

2-71110081-CT-CTT

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over