NM_000255.4:c.656A>G

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Moderate

The NM_000255.4(MMUT):​c.656A>G​(p.Asn219Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,248 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. N219Y) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

MMUT
NM_000255.4 missense

Scores

12
4
1

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1U:1

Conservation

PhyloP100: 7.56

Publications

0 publications found
Variant links:
Genes affected
MMUT (HGNC:7526): (methylmalonyl-CoA mutase) This gene encodes the mitochondrial enzyme methylmalonyl Coenzyme A mutase. In humans, the product of this gene is a vitamin B12-dependent enzyme which catalyzes the isomerization of methylmalonyl-CoA to succinyl-CoA, while in other species this enzyme may have different functions. Mutations in this gene may lead to various types of methylmalonic aciduria. [provided by RefSeq, Jul 2008]
MMUT Gene-Disease associations (from GenCC):
  • methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), G2P
  • vitamin B12-unresponsive methylmalonic acidemia type mut-
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • vitamin B12-unresponsive methylmalonic acidemia type mut0
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 13 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_000255.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr6-49457789-T-A is described in ClinVar as [Pathogenic]. Clinvar id is 1886.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 150 curated pathogenic missense variants (we use a threshold of 10). The gene has 9 curated benign missense variants. Gene score misZ: 0.22855 (below the threshold of 3.09). Trascript score misZ: 1.0842 (below the threshold of 3.09). GenCC associations: The gene is linked to vitamin B12-unresponsive methylmalonic acidemia type mut-, methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency, vitamin B12-unresponsive methylmalonic acidemia type mut0.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.969
PP5
Variant 6-49457788-T-C is Pathogenic according to our data. Variant chr6-49457788-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 567826.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMUTNM_000255.4 linkc.656A>G p.Asn219Ser missense_variant Exon 3 of 13 ENST00000274813.4 NP_000246.2 P22033A0A024RD82B2R6K1
MMUTXM_005249143.4 linkc.656A>G p.Asn219Ser missense_variant Exon 3 of 13 XP_005249200.1 P22033A0A024RD82

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMUTENST00000274813.4 linkc.656A>G p.Asn219Ser missense_variant Exon 3 of 13 1 NM_000255.4 ENSP00000274813.3 P22033

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152194
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.00000797
AC:
2
AN:
251044
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461054
Hom.:
0
Cov.:
30
AF XY:
0.00000413
AC XY:
3
AN XY:
726870
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33458
American (AMR)
AF:
0.0000447
AC:
2
AN:
44708
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39674
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86200
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53398
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000720
AC:
8
AN:
1111358
Other (OTH)
AF:
0.00
AC:
0
AN:
60370
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.415
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.00000657
AC:
1
AN:
152194
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74346
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Pathogenic:1
Feb 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 219 of the MUT protein (p.Asn219Ser). This variant is present in population databases (no rsID available, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with MUT-related conditions. ClinVar contains an entry for this variant (Variation ID: 567826). 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 MUT protein function with a positive predictive value of 95%. This variant disrupts the p.Asn219 amino acid residue in MUT. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11528502, 16281286, 17113806). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Methylmalonic aciduria due to complete methylmalonyl-CoA mutase deficiency Uncertain:1
Aug 18, 2021
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Uncertain
0.11
D
BayesDel_noAF
Uncertain
0.10
CADD
Pathogenic
26
DANN
Uncertain
1.0
Eigen
Pathogenic
0.99
Eigen_PC
Pathogenic
0.89
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D
M_CAP
Pathogenic
0.45
D
MetaRNN
Pathogenic
0.97
D
MetaSVM
Pathogenic
1.1
D
PhyloP100
7.6
PrimateAI
Pathogenic
0.87
D
PROVEAN
Pathogenic
-5.0
D
REVEL
Pathogenic
0.91
Sift
Uncertain
0.0010
D
Sift4G
Pathogenic
0.0010
D
Vest4
0.90
MutPred
0.86
Gain of disorder (P = 0.1103);
MVP
0.99
MPC
0.41
ClinPred
0.99
D
GERP RS
5.5
gMVP
0.95
Mutation Taster
=78/22
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: rs950211877; hg19: chr6-49425501; API