chr6-49459144-C-T

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_000255.4(MMUT):​c.323G>A​(p.Arg108His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000204 in 1,614,108 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R108C) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000020 ( 0 hom. )

Consequence

MMUT
NM_000255.4 missense

Scores

15
1
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:9O:1

Conservation

PhyloP100: 7.50

Publications

29 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 19 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 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 chr6-49459145-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 1887.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, 0.987
PP5
Variant 6-49459144-C-T is Pathogenic according to our data. Variant chr6-49459144-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 100707.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMUTNM_000255.4 linkc.323G>A p.Arg108His missense_variant Exon 2 of 13 ENST00000274813.4 NP_000246.2
MMUTXM_005249143.4 linkc.323G>A p.Arg108His missense_variant Exon 2 of 13 XP_005249200.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMUTENST00000274813.4 linkc.323G>A p.Arg108His missense_variant Exon 2 of 13 1 NM_000255.4 ENSP00000274813.3

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152146
Hom.:
0
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:
0.000193
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251292
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000198
AC:
29
AN:
1461844
Hom.:
0
Cov.:
31
AF XY:
0.0000179
AC XY:
13
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000234
AC:
26
AN:
1111984
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
2
3
5
6
8
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:
0.0000263
AC:
4
AN:
152264
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74436
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41560
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5180
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
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:
0.0000272
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.00000824
AC:
1
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:9Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency Pathogenic:4
-
Juno Genomics, Hangzhou Juno Genomics, Inc
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PM3_VeryStrong+PP4+PM2_Supporting+PP3_Strong+PM5 -

Oct 07, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 03, 2017
Counsyl
Significance:Pathogenic
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. -

-
Neonatal Disease Screening Center, Medical Genetics Center, Huaihua City Maternal and Child Health Care Hospital
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

PM2_P+PM3_VS+PP3+PP4 -

not provided Pathogenic:2Other:1
Mar 03, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 17113806, 17075691, 25959030, 26454439, 25750861, 16435223, 27233228, 22661206, 23430940, 31466887, 35361390, 15643616, 21671183, 30098236, 31622506, 33413471, 33453710, 35223700, 11528502, 29731766, 32005694, 31998365, 27167370, 16281286, 26018627, 32754920) -

Aug 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 108 of the MUT protein (p.Arg108His). This variant is present in population databases (rs483352778, gnomAD 0.007%). This missense change has been observed in individual(s) with methylmalonic aciduria (PMID: 11528502, 16281286, 17113806). ClinVar contains an entry for this variant (Variation ID: 100707). 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.Arg108 amino acid residue in MUT. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 2661559, 16281286, 17075691, 22614770, 23045948, 24059531, 24464670, 27578510). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

-
Medical Genetics Unit, Ain Shams University Pediatrics Hospital
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Methylmalonic aciduria due to complete methylmalonyl-CoA mutase deficiency Pathogenic:1
Sep 16, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Methylmalonic acidemia Pathogenic:1
Nov 10, 2017
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: The MUT c.323G>A (p.Arg108His) variant involves the alteration of a conserved nucleotide located at the SB, substrate binding (beta alpha) 8 barrel domain (Lempp_2007). 4/4 in silico tools predict a damaging outcome for this variant (SNPsandGO not captured due to low reliability index). This variant was found in 6/246336 control chromosomes at a frequency of 0.0000244, which does not exceed the estimated maximal expected allele frequency of a pathogenic MUT variant (0.0024152). This variant has been reported in multiple affected individuals mostly as compound heterozygotes and the patients' fibroblasts presented with a marked decrease in MCM enzyme activity (Acquaviva_2001 and Lempp_2007). Variants involving codon R108 (p.R108C, p.R108G, and p.R108H) have been reported in multiple patients with Methylmalonic aciduria suggesting it is a mutation hotspot. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -

METHYLMALONIC ACIDURIA, mut(0) TYPE Pathogenic:1
Dec 21, 2016
Genetic Services Laboratory, University of Chicago
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.46
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
32
DANN
Pathogenic
1.0
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.84
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D
M_CAP
Pathogenic
0.45
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Pathogenic
0.98
D
PhyloP100
7.5
PrimateAI
Pathogenic
0.87
D
PROVEAN
Pathogenic
-4.9
D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Vest4
0.98
MutPred
1.0
Loss of MoRF binding (P = 0.0708);
MVP
0.98
MPC
0.54
ClinPred
1.0
D
GERP RS
5.6
gMVP
0.93
Mutation Taster
=19/81
disease causing (ClinVar)

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: rs483352778; hg19: chr6-49426857; COSMIC: COSV51277513; COSMIC: COSV51277513; API