6-49440295-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_000255.4(MMUT):​c.1867G>A​(p.Gly623Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,898 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/19 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

MMUT
NM_000255.4 missense

Scores

16
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:7O:1

Conservation

PhyloP100: 7.57
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 16 ACMG points.

PM1
In a domain B12-binding (size 132) in uniprot entity MUTA_HUMAN there are 17 pathogenic changes around while only 1 benign (94%) in NM_000255.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.964
PP5
Variant 6-49440295-C-T is Pathogenic according to our data. Variant chr6-49440295-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 1884.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
MMUTNM_000255.4 linkuse as main transcriptc.1867G>A p.Gly623Arg missense_variant 11/13 ENST00000274813.4 NP_000246.2 P22033A0A024RD82B2R6K1
MMUTXM_005249143.4 linkuse as main transcriptc.1867G>A p.Gly623Arg missense_variant 11/13 XP_005249200.1 P22033A0A024RD82

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
MMUTENST00000274813.4 linkuse as main transcriptc.1867G>A p.Gly623Arg missense_variant 11/131 NM_000255.4 ENSP00000274813.3 P22033

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152136
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000145
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000796
AC:
2
AN:
251316
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135820
show subpopulations
Gnomad AFR exome
AF:
0.000123
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461762
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727200
show subpopulations
Gnomad4 AFR exome
AF:
0.000120
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152136
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74316
show subpopulations
Gnomad4 AFR
AF:
0.000145
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:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000134
Hom.:
1
Bravo
AF:
0.0000416
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingGeneDxNov 20, 2019Reported to be a common variant in individuals of African descent and functional analysis of G623R found that it is associated with significantly reduced enzyme activity compared to wild-type (Worgan et al., 2006; Janata et al., 1997).; In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Not observed at a significant frequency in large population cohorts (Lek et al., 2016); The majority of missense variants in this gene are considered pathogenic (Stenson et al., 2014); This variant is associated with the following publications: (PMID: 15643616, 7909321, 19375370, 17113806, 31525265, 25087612, 9285782, 8990001, 16281286) -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 01, 2021This sequence change replaces glycine with arginine at codon 623 of the MUT protein (p.Gly623Arg). The glycine residue is highly conserved and there is a moderate physicochemical difference between glycine and arginine. This variant is present in population databases (rs121918254, ExAC 0.01%). This missense change has been observed in individuals with methylmalonic aciduria (PMID: 7909321, 15643616, 16281286, 19375370). ClinVar contains an entry for this variant (Variation ID: 1884). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. Experimental studies have shown that this missense change affects MUT function (PMID: 7909321). For these reasons, this variant has been classified as Pathogenic. -
Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency Pathogenic:1Other:1
not provided, no classification providedliterature onlyGeneReviews-- -
Likely pathogenic, no assertion criteria providedclinical testingCounsylMar 17, 2017- -
MMUT-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesAug 14, 2024The MMUT c.1867G>A variant is predicted to result in the amino acid substitution p.Gly623Arg. This variant has been reported in the homozygous state or heterozygous state with a second MMUT variant in multiple individuals with methylmalonic acidemia (see for example, Qureshi et al. 1994. PubMed ID: 7909321; Worgan et al. 2006. PubMed ID: 16281286; Brassier et al. 2020. PubMed ID: 31525265). In homozygous patients, this variant was associated with a mut0 phenotype (Worgan et al. 2006. PubMed ID: 16281286). This variant is reported in 0.012% of alleles in individuals of African descent in gnomAD. An in vitro experimental study suggests this variant reduces enzyme activity to 3% of wildtype (Janata et al. 1997. PubMed ID: 9285782). This variant is interpreted as pathogenic. -
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, LabCorpJun 13, 2022Variant summary: MUT c.1867G>A (p.Gly623Arg) results in a non-conservative amino acid change located in the Cobalamin (vitamin B12)-binding domain (IPR006158) 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 8e-06 in 251316 control chromosomes. c.1867G>A has been reported in the literature in multiple individuals affected with Methylmalonic Acidemia supported by characteristic biochemical findings (example, Acquaiva_2005, Worgan_2006, Brassier_2020). These data indicate that the variant is very likely to be associated with disease. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
METHYLMALONIC ACIDURIA, mut(0) TYPE Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMApr 01, 1994- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.44
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
31
DANN
Pathogenic
1.0
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
1.0
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
1.0
D
M_CAP
Pathogenic
0.40
D
MetaRNN
Pathogenic
0.96
D
MetaSVM
Pathogenic
1.1
D
PrimateAI
Pathogenic
0.93
D
PROVEAN
Pathogenic
-7.8
D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Vest4
1.0
MutPred
0.92
Loss of ubiquitination at K621 (P = 0.0259);
MVP
0.99
MPC
0.53
ClinPred
1.0
D
GERP RS
5.7
gMVP
0.96

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

LitVar

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

Other links and lift over

dbSNP: rs121918254; hg19: chr6-49408008; API