Variant 6-49448840-G-A details in Genebe, Genetics Data Aggregator

Variant summary

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

The NM_000255.4(MMUT):c.1420C>T(p.Arg474Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000753 in 1,461,044 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: not found (cov: 32)

Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

MMUT
NM_000255.4 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 6.52

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 links:

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 6-49448840-G-A is Pathogenic according to our data. Variant chr6-49448840-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 554873.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr6-49448840-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MMUT	NM_000255.4 linkuse as main transcript	c.1420C>T	p.Arg474Ter	stop_gained	7/13	ENST00000274813.4	NP_000246.2
MMUT	XM_005249143.4 linkuse as main transcript	c.1420C>T	p.Arg474Ter	stop_gained	7/13		XP_005249200.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MMUT	ENST00000274813.4 linkuse as main transcript	c.1420C>T	p.Arg474Ter	stop_gained	7/13	1	NM_000255.4	ENSP00000274813	P1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000796

AC:

AN:

251244

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135796

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:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000753

AC:

AN:

1461044

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

726872

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000720

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.00000756

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 07, 2023

This sequence change creates a premature translational stop signal (p.Arg474*) 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 (no rsID available, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with methylmalonic aciduria (PMID: 15643616, 16281286). ClinVar contains an entry for this variant (Variation ID: 554873). For these reasons, this variant has been classified as Pathogenic. -

MMUT-related disorder

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Sep 18, 2024

The MMUT c.1420C>T variant is predicted to result in premature protein termination (p.Arg474*). This variant has been reported in the homozygous state or heterozygous state with a second MMUT variant in individuals with methylmalonic acidemia, typically mmut0 type (Acquaviva et al. 2005. PubMed ID: 15643616; Worgan et al. 2006. PubMed ID: 16281286). This variant is reported in 0.0033% of alleles in individuals of South Asian descent in gnomAD. Nonsense variants in MMUT are expected to be pathogenic. This variant is interpreted as pathogenic. -

Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Counsyl

Nov 08, 2017

- -

Methylmalonic aciduria due to complete methylmalonyl-CoA mutase deficiency

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Sep 16, 2020

- -

Methylmalonic acidemia

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Dec 20, 2019

Variant summary: MUT c.1420C>T (p.Arg474X) 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. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 8e-06 in 251244 control chromosomes (gnomAD). c.1420C>T has been reported in the literature in multiple homozygous and compound heterozygous individuals affected with Methylmalonic Acidemia (e.g. Acquaviva_2015, Forny_2016, Worgan_2006). These data indicate that the variant is very likely to be associated with disease. Biochemical studies report low incorporation of propionate and low MUT enzyme activity for cells with the variant and assign mut0 class (Forny_2016, Worgan_2006). Two ClinVar submitters (evaluation after 2014) cite 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

0.56

BayesDel_noAF

Pathogenic

0.65

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

0.86

Eigen_PC

Pathogenic

0.74

FATHMM_MKL

Pathogenic

0.99

MutationTaster

Benign

1.0

Vest4

0.97

GERP RS

5.1

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over