NM_022132.5:c.1309A>G

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PM2PP5

The NM_022132.5(MCCC2):c.1309A>G(p.Ile437Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000421 in 1,614,094 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000043 ( 0 hom. )

Consequence

MCCC2
NM_022132.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:2

Conservation

PhyloP100: 7.45

Variant links:

Genes affected

MCCC2 (HGNC:6937): (methylcrotonyl-CoA carboxylase subunit 2) This gene encodes the small subunit of 3-methylcrotonyl-CoA carboxylase. This enzyme functions as a heterodimer and catalyzes the carboxylation of 3-methylcrotonyl-CoA to form 3-methylglutaconyl-CoA. Mutations in this gene are associated with 3-Methylcrotonylglycinuria, an autosomal recessive disorder of leucine catabolism. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, May 2018]

MCCC2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM1

In a domain CoA carboxyltransferase C-terminal (size 246) in uniprot entity MCCB_HUMAN there are 17 pathogenic changes around while only 0 benign (100%) in NM_022132.5

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 5-71649189-A-G is Pathogenic according to our data. Variant chr5-71649189-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 1925.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=1, Likely_pathogenic=1}. Variant chr5-71649189-A-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MCCC2	NM_022132.5 link	c.1309A>G	p.Ile437Val	missense_variant	Exon 14 of 17	ENST00000340941.11	NP_071415.1	Q9HCC0-1A0A140VK29
MCCC2	NM_001363147.1 link	c.1195A>G	p.Ile399Val	missense_variant	Exon 13 of 16		NP_001350076.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MCCC2	ENST00000340941.11 link	c.1309A>G	p.Ile437Val	missense_variant	Exon 14 of 17	1	NM_022132.5	ENSP00000343657.6		Q9HCC0-1

Frequencies

GnomAD3 genomes

AF:

0.0000328

AC:

AN:

152226

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:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251480

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

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:

0.0000352

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000431

AC:

AN:

1461868

Hom.:

Cov.:

AF XY:

0.0000399

AC XY:

AN XY:

727234

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

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:

0.0000558

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000328

AC:

AN:

152226

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74374

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:

0.0000735

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000381

Hom.:

Bravo

AF:

0.0000453

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:5Uncertain:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

3-methylcrotonyl-CoA carboxylase 2 deficiency

Pathogenic:3Uncertain:2

Mar 25, 2024

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 30, 2020

Natera, Inc.

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Feb 01, 2001

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Jan 26, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 437 of the MCCC2 protein (p.Ile437Val). RNA analysis indicates that this missense change induces altered splicing and may result in an absent or altered protein product. This variant is present in population databases (rs119103224, gnomAD 0.005%). This missense change has been observed in individual(s) with 3 methylcrotonyl-CoA carboxylase deficiency (PMID: 22642865; internal data). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 1925). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt MCCC2 protein function with a negative predictive value of 80%. Studies have shown that this missense change results in activation of a cryptic donor site, and produces a non-functional protein and/or introduces a premature termination codon (PMID: 11181649). For these reasons, this variant has been classified as Pathogenic. -

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The MCCC2 c.1309A>G (p.Ile437Val) variant is described in two studies in which it is found in a compound heterozygous state in one individual and in a heterozygous state in another individual, both with 3-methylcrotonyl-CoA carboxylase (3-MCC) deficiency (Baumgartner et al. 2001; GrÃ¼nert et al. 2012). The p.Ile437Val variant was not present in 100 controls (GrÃ¼nert et al. 2012) and is reported at a frequency of 0.00005 in the European (non-Finnish) population of the Genome Aggregation Database. Functional studies using RT-PCR showed that the p.Ile437Val variant activates a cryptic splice donor site, which when used results in the deletion of the last 64 base pairs of exon 14 from the mature transcript. Direct sequencing of the RT-PCR product showed that virtually all the transcript present uses the new donor site (Baumgartner et al. 2001). Based on the evidence, the p.Ile437Val variant is classified as a variant of unknown significance but suspicious for pathogenicity for 3-MCC deficiency. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

not provided

Pathogenic:2

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.091

BayesDel_addAF

Pathogenic

0.21

BayesDel_noAF

Pathogenic

0.24

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.65

D;.

Eigen

Uncertain

0.28

Eigen_PC

Uncertain

0.40

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.98

D;D

M_CAP

Benign

0.080

MetaRNN

Uncertain

0.60

D;D

MetaSVM

Pathogenic

0.88

MutationAssessor

Benign

1.1

L;.

PrimateAI

Uncertain

0.66

PROVEAN

Benign

-0.94

N;N

REVEL

Pathogenic

0.74

Sift

Benign

0.049

D;T

Sift4G

Benign

0.11

T;T

Polyphen

0.29

B;.

Vest4

0.83

MVP

0.92

MPC

0.11

ClinPred

0.19

GERP RS

5.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.24

gMVP

0.60

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.69

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.69

Position offset: -1

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.

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