rs777031588

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2PP3PP5_Very_Strong

The NM_000255.4(MMUT):c.1084-10A>G variant causes a splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,613,178 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

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

Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

MMUT
NM_000255.4 splice_polypyrimidine_tract, intron

Scores

Splicing: ADA: 0.9996

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 0.105

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 11 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

PP5

Variant 6-49451724-T-C is Pathogenic according to our data. Variant chr6-49451724-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 203845.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MMUT	NM_000255.4 linkuse as main transcript	c.1084-10A>G		splice_polypyrimidine_tract_variant, intron_variant		ENST00000274813.4
MMUT	XM_005249143.4 linkuse as main transcript	c.1084-10A>G		splice_polypyrimidine_tract_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MMUT	ENST00000274813.4 linkuse as main transcript	c.1084-10A>G		splice_polypyrimidine_tract_variant, intron_variant		1	NM_000255.4	P1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152120

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

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

GnomAD3 exomes

AF:

0.0000322

AC:

AN:

248136

Hom.:

AF XY:

0.0000446

AC XY:

AN XY:

134414

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000546

Gnomad SAS exome

AF:

0.000164

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000180

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000192

AC:

AN:

1461058

Hom.:

Cov.:

AF XY:

0.0000248

AC XY:

AN XY:

726854

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000360

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152120

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74316

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000338

Hom.:

Bravo

AF:

0.0000151

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 28, 2024	This sequence change falls in intron 5 of the MUT gene. It does not directly change the encoded amino acid sequence of the MUT protein. This variant is present in population databases (rs777031588, gnomAD 0.02%). This variant has been observed in individual(s) with methylmalonic aciduria (PMID: 23430940; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 203845). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 16, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 17, 2021	Published functional studies demonstrate c.1084-10 A>G results in activation of a cryptic splice site, supporting a damaging effect (Forny et al., 2016; Brasil et al., 2018); This variant is associated with the following publications: (PMID: 27167370, 30041674, 23430940, 31622506, 27535533, 27591164) -

Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency

Pathogenic:2

Likely pathogenic, no assertion criteria provided	clinical testing	Counsyl	Aug 30, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jul 18, 2023	- -

Methylmalonic acidemia

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Dec 08, 2022	Variant summary: MUT c.1084-10A>G alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Several computational tools predict a significant impact on normal splicing: Three predict the variant abolishes/weakens a 3' acceptor site, and four predict it creates a new cryptic intronic 3' acceptor site. Experimental evidence supports these predictions demonstrating that this variant affects mRNA splicing (Forny_2016 and Brasil_2018). The variant allele was found at a frequency of 3.2e-05 in 248136 control chromosomes (gnomAD). c.1084-10A>G has been reported in the literature in the homozygous and compound heterozygous states in multiple individuals affected with Methylmalonic Acidemia (e.g. Liu_2012, Forny_2016, Devi_2017). These data indicate that the variant is very likely to be associated with disease. One publication reports a homozygous patient with less than 10% activity of Methylmalonyl-CoA mutase when compared to reference range (Forny_2016). Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic (n=4) and likely pathogenic (n=1). Based on the evidence outlined above, the variant was classified as pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Jun 30, 2022	The c.1084-10A>G variant in MMUT has been reported in 3 compound heterozygote individuals and 1 homozygous individual with methylmalonic aciduria (Liu 2012 PMID: 23430940, Forny 2016 PMID: 27167370, Yu 2021 PMID: 34668645). It has also been identified in 0.02% (1/4828) of South Asian and 0.004% (2/41418) of African chromosomes by gnomAD v. 3 (http://gnomad.broadinstitute.org). This variant has also been reported in ClinVar (Variation ID 203845). Studies have shown that this variant activates a cryptic splice site in intron 5 of the MMUT gene leading to an insertion that would disrupt the protein (Forny 2016 PMID: 27167370, Brasil 2018 PMID: 30041674). In summary, although additional studies are required to fully establish its clinical significance, this variant meets criteria to be classified as likely pathogenic for autosomal recessive methylmalonic acidemia. ACMG/AMP Criteria applied: PM3_S, PS3_M. -

Methylmalonic aciduria due to complete methylmalonyl-CoA mutase deficiency

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Mar 02, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.66

Cadd

Benign

Dann

Benign

0.88

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.2

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.96

SpliceAI score (max)

0.98

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.98

Position offset: -1

DS_AL_spliceai

0.74

Position offset: -10

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