rs1183369398

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1PM2PP2

The NM_000255.4(MMUT):​c.2197G>A​(p.Val733Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000316 in 1,613,804 control chromosomes in the GnomAD database, with no homozygous occurrence. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

MMUT
NM_000255.4 missense

Scores

2
15

Clinical Significance

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

Conservation

PhyloP100: 0.805

Publications

2 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: Uncertain_significance. The variant received 5 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, 5 uncertain in NM_000255.4
PM2
Very rare variant in population databases, with high coverage;
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.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMUTNM_000255.4 linkc.2197G>A p.Val733Ile missense_variant Exon 13 of 13 ENST00000274813.4 NP_000246.2 P22033A0A024RD82B2R6K1
MMUTXM_005249143.4 linkc.2197G>A p.Val733Ile missense_variant Exon 13 of 13 XP_005249200.1 P22033A0A024RD82

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMUTENST00000274813.4 linkc.2197G>A p.Val733Ile missense_variant Exon 13 of 13 1 NM_000255.4 ENSP00000274813.3 P22033

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152118
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:
0.0000944
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251390
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000274
AC:
40
AN:
1461686
Hom.:
0
Cov.:
30
AF XY:
0.0000179
AC XY:
13
AN XY:
727150
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39678
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53412
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000360
AC:
40
AN:
1111860
Other (OTH)
AF:
0.00
AC:
0
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.441
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.0000723
AC:
11
AN:
152118
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74290
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41426
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.0000944
AC:
1
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000147
AC:
10
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.000287
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Nov 01, 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: MUT (aka. MMUT) c.2197G>A (p.Val733Ile) results in a conservative amino acid change located in the cobalamin (vitamin B12)-binding domain (IPR006158) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 2.4e-05 in 251390 control chromosomes (gnomAD). c.2197G>A has been reported in the literature in the heterozygous state in a consanguineous couple who had lost two children in infancy, both with clinical symptoms suggestive of Methylmalonic Acidemia (Paleja_2015). These data do not allow clear conclusions about the significance of the variant. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One clinical diagnostic laboratory has submitted a clinical-significance assessment for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided Uncertain:1
Nov 06, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 733 of the MUT protein (p.Val733Ile). This variant is present in population databases (no rsID available, gnomAD 0.01%). This missense change has been observed in individual(s) with methylmalonic acidemia (PMID: 26174677). ClinVar contains an entry for this variant (Variation ID: 552549). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The isoleucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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. -

Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency Uncertain:1
Jun 14, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.068
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.36
CADD
Benign
8.3
DANN
Benign
0.81
Eigen
Benign
-1.2
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.21
N
LIST_S2
Benign
0.78
T
M_CAP
Uncertain
0.10
D
MetaRNN
Uncertain
0.48
T
MetaSVM
Benign
-0.91
T
PhyloP100
0.81
PrimateAI
Benign
0.25
T
PROVEAN
Benign
0.020
N
REVEL
Benign
0.23
Sift
Benign
0.30
T
Sift4G
Benign
0.34
T
Vest4
0.67
MVP
0.71
MPC
0.074
ClinPred
0.031
T
GERP RS
-0.83
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
gMVP
0.56
Mutation Taster
=39/61
disease causing

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

Other links and lift over

dbSNP: rs1183369398; hg19: chr6-49399497; API