3-183086767-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2PP3_StrongPP5

The NM_020166.5(MCCC1):​c.295G>A​(p.Gly99Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000266 in 1,613,918 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. G99R) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

MCCC1
NM_020166.5 missense

Scores

10
4
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 7.45

Publications

4 publications found
Variant links:
Genes affected
MCCC1 (HGNC:6936): (methylcrotonyl-CoA carboxylase subunit 1) This gene encodes the large 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. [provided by RefSeq, Jul 2008]
MCCC1 Gene-Disease associations (from GenCC):
  • 3-methylcrotonyl-CoA carboxylase 1 deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • 3-methylcrotonyl-CoA carboxylase deficiency
    Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.956
PP5
Variant 3-183086767-C-T is Pathogenic according to our data. Variant chr3-183086767-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 656280.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MCCC1NM_020166.5 linkc.295G>A p.Gly99Ser missense_variant Exon 4 of 19 ENST00000265594.9 NP_064551.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MCCC1ENST00000265594.9 linkc.295G>A p.Gly99Ser missense_variant Exon 4 of 19 1 NM_020166.5 ENSP00000265594.4

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152132
Hom.:
0
Cov.:
32
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251214
AF XY:
0.0000295
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000163
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000253
AC:
37
AN:
1461786
Hom.:
0
Cov.:
31
AF XY:
0.0000206
AC XY:
15
AN XY:
727180
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39692
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86226
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53404
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000306
AC:
34
AN:
1111972
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.445
Heterozygous variant carriers
0
3
6
8
11
14
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
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
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152132
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74310
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41396
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
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:
0.0000282
Hom.:
0
Bravo
AF:
0.0000264
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

3-methylcrotonyl-CoA carboxylase 1 deficiency Pathogenic:1Uncertain:1
Jan 23, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Jul 17, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. 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 MCCC1 protein function. ClinVar contains an entry for this variant (Variation ID: 656280). This missense change has been observed in individual(s) with 3 Methylcrotonyl-CoA carboxylase deficiency (PMID: 25190158, 31730530; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (rs375244642, gnomAD 0.02%). This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 99 of the MCCC1 protein (p.Gly99Ser).

not specified Uncertain:1
Jul 31, 2024
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: MCCC1 c.295G>A (p.Gly99Ser) results in a non-conservative amino acid change located in the biotin carboxylase-like, N-terminal domain (IPR005481) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2.4e-05 in 251214 control chromosomes. c.295G>A has been reported in the literature in individuals identified through newborn screening programs as affected with Methylcrotonyl-CoA Carboxylase Deficiency, including at least one case where it was found in trans with a pathogenic variant (e.g. Ye_2014, Wang_2019, Yang_2019, Cheng_2023). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 36822454, 31730530, 30838026, 25190158). ClinVar contains an entry for this variant (Variation ID: 656280). 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
AlphaMissense
Benign
0.29
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.51
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.82
D;D;D
Eigen
Pathogenic
0.73
Eigen_PC
Uncertain
0.58
LIST_S2
Pathogenic
1.0
D;D;D
M_CAP
Uncertain
0.18
D
MetaRNN
Pathogenic
0.96
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
0.0
.;.;.
PhyloP100
7.5
PrimateAI
Uncertain
0.65
T
PROVEAN
Pathogenic
-5.6
D;.;D
Sift
Pathogenic
0.0
D;.;D
Sift4G
Pathogenic
0.0
D;D;.
Vest4
0.97
ClinPred
0.97
D
GERP RS
5.5
Varity_R
0.96
gMVP
0.83
Mutation Taster
=11/89
disease causing

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: rs375244642; hg19: chr3-182804555; API