6-49451591-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000255.4(MMUT):​c.1207C>T​(p.Arg403Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000781 in 1,613,942 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000082 ( 0 hom. )

Consequence

MMUT
NM_000255.4 stop_gained

Scores

4
2
1

Clinical Significance

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

Conservation

PhyloP100: 6.86
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-49451591-G-A is Pathogenic according to our data. Variant chr6-49451591-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 167310.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr6-49451591-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
MMUTNM_000255.4 linkuse as main transcriptc.1207C>T p.Arg403Ter stop_gained 6/13 ENST00000274813.4
MMUTXM_005249143.4 linkuse as main transcriptc.1207C>T p.Arg403Ter stop_gained 6/13

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
MMUTENST00000274813.4 linkuse as main transcriptc.1207C>T p.Arg403Ter stop_gained 6/131 NM_000255.4 P1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152118
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000398
AC:
10
AN:
251338
Hom.:
0
AF XY:
0.0000589
AC XY:
8
AN XY:
135834
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000792
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000821
AC:
120
AN:
1461824
Hom.:
0
Cov.:
31
AF XY:
0.0000784
AC XY:
57
AN XY:
727208
show subpopulations
Gnomad4 AFR exome
AF:
0.0000597
Gnomad4 AMR exome
AF:
0.0000447
Gnomad4 ASJ exome
AF:
0.0000383
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000989
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152118
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74308
show subpopulations
Gnomad4 AFR
AF:
0.0000724
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000891
Hom.:
0
Bravo
AF:
0.0000453
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.000109
EpiControl
AF:
0.000178

ClinVar

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

Submissions by phenotype

not provided Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 01, 2024This sequence change creates a premature translational stop signal (p.Arg403*) in the MUT gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in MUT are known to be pathogenic (PMID: 15781192). This variant is present in population databases (rs727504020, gnomAD 0.02%). This premature translational stop signal has been observed in individuals with MUT-related conditions (PMID: 12402345, 17113806, 26790480, 27167370, 27233228). ClinVar contains an entry for this variant (Variation ID: 167310). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Dec 04, 2013- -
Pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenNov 01, 2021- -
Pathogenic, criteria provided, single submitterclinical testingGeneDxSep 26, 2022A mouse model carrying the equivalent variant, in the homozygous state, in murine MUT had features which mimicked human methylmalonic acidemia (Buck et al., 2012).; Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 17113806, 26790480, 27233228, 23024777, 25525159, 12402345, 27167370, 31622506, 35361390, 33413471) -
Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency Pathogenic:3
Pathogenic, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineDec 22, 2014The p.Arg403X variant in MUT has been reported in 1 individual with clinical features of methylmalonic acidemia and no enzyme activity, though a second allele was not identified (Peters 2002). This variant has also been identified in 1/67564 of European chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org). Animal models in mice have shown that this variant causes features of the disease (Buck 2012). This nonsense variant leads to a premature termination codon at position 403, which is predicted to lead to a truncated or absent protein. Homozygous or compound heterozygous loss of function of MUT has been shown to cause methylmalonic acidemia. In summary, this variant meets our criteria to be classified as pathogenic for methylmalonic acidemia in an autosomal recessive manner. -
Pathogenic, criteria provided, single submitterclinical testingCounsylFeb 17, 2017- -
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsMar 28, 2022- -
Methylmalonic aciduria due to complete methylmalonyl-CoA mutase deficiency Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -
Methylmalonic acidemia Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpDec 26, 2019Variant summary: MUT c.1207C>T (p.Arg403X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 4e-05 in 251338 control chromosomes (gnomAD). This frequency is not significantly higher than expected for a pathogenic variant in MUT causing Methylmalonic Acidemia (4e-05 vs 0.0024). c.1207C>T has been reported in the literature in several individuals affected with Methylmalonic Acidemia (e.g. Worgan_2006, Forny_2016). These data indicate that the variant is very likely to be associated with disease. These studies also reported experimental evidence evaluating an impact on protein function, and demonstrated the variant results in <10% of normal activity (Worgan_2006, Forny_2016). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation, and both of them classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.65
CADD
Pathogenic
37
DANN
Uncertain
1.0
Eigen
Pathogenic
0.79
Eigen_PC
Uncertain
0.66
FATHMM_MKL
Pathogenic
0.98
D
MutationTaster
Benign
1.0
A
Vest4
0.94
GERP RS
4.6

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs727504020; hg19: chr6-49419304; COSMIC: COSV51279996; API