rs371374378

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_022132.5(MCCC2):​c.1282G>A​(p.Ala428Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000062 in 1,614,038 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A428A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00011 ( 1 hom., cov: 32)
Exomes 𝑓: 0.000057 ( 0 hom. )

Consequence

MCCC2
NM_022132.5 missense

Scores

13
5
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 8.12

Publications

5 publications found
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 Gene-Disease associations (from GenCC):
  • 3-methylcrotonyl-CoA carboxylase 2 deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • 3-methylcrotonyl-CoA carboxylase deficiency
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_022132.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.94

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MCCC2NM_022132.5 linkc.1282G>A p.Ala428Thr missense_variant Exon 14 of 17 ENST00000340941.11 NP_071415.1 Q9HCC0-1A0A140VK29
MCCC2NM_001363147.1 linkc.1168G>A p.Ala390Thr missense_variant Exon 13 of 16 NP_001350076.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MCCC2ENST00000340941.11 linkc.1282G>A p.Ala428Thr missense_variant Exon 14 of 17 1 NM_022132.5 ENSP00000343657.6 Q9HCC0-1

Frequencies

GnomAD3 genomes
AF:
0.000112
AC:
17
AN:
152240
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.000565
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000636
AC:
16
AN:
251478
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.000185
Gnomad NFE exome
AF:
0.0000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000568
AC:
83
AN:
1461798
Hom.:
0
Cov.:
32
AF XY:
0.0000550
AC XY:
40
AN XY:
727196
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.000131
AC:
7
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000639
AC:
71
AN:
1111926
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
Heterozygous variant carriers
0
6
12
19
25
31
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000112
AC:
17
AN:
152240
Hom.:
1
Cov.:
32
AF XY:
0.000175
AC XY:
13
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41472
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.000565
AC:
6
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000147
AC:
10
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000818
Hom.:
0
Bravo
AF:
0.0000567
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000494
AC:
6
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Jul 22, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1282G>A (p.A428T) alteration is located in exon 14 (coding exon 14) of the MCCC2 gene. This alteration results from a G to A substitution at nucleotide position 1282, causing the alanine (A) at amino acid position 428 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Methylcrotonyl-CoA carboxylase deficiency Uncertain:1
Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

3-methylcrotonyl-CoA carboxylase 2 deficiency Uncertain:1
Jun 22, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 428 of the MCCC2 protein (p.Ala428Thr). This variant is present in population databases (rs371374378, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with MCCC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 569797). 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 MCCC2 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.34
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.53
CADD
Uncertain
23
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.93
D;.
Eigen
Pathogenic
0.89
Eigen_PC
Pathogenic
0.75
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D;D
M_CAP
Pathogenic
0.53
D
MetaRNN
Pathogenic
0.94
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.9
H;.
PhyloP100
8.1
PrimateAI
Uncertain
0.59
T
PROVEAN
Uncertain
-3.9
D;D
REVEL
Pathogenic
0.93
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;.
Vest4
0.85
MVP
0.99
MPC
0.50
ClinPred
0.98
D
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.79
gMVP
0.92
Mutation Taster
=84/16
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs371374378; hg19: chr5-70944989; COSMIC: COSV60155677; API