6-49444660-G-A

Variant names:

• chr6-49444660-G-A
• rs879253845
• NM_000255.4:c.1655C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Moderate PP5_Moderate

The NM_000255.4(MMUT):​c.1655C>T​(p.Ala552Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000103 in 1,460,998 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: MMUT NM_000255.4 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.64
• Publications: 2 publications found

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

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000255.4
• PM2: Very rare variant in population databases, with high coverage
• 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, 0.862
• PP5: Variant 6-49444660-G-A is Pathogenic according to our data. Variant chr6-49444660-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 222935.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000255.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MMUT	NM_000255.4	MANE Select	c.1655C>T	p.Ala552Val	missense	Exon 9 of 13	NP_000246.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MMUT	ENST00000274813.4	TSL:1 MANE Select	c.1655C>T	p.Ala552Val	missense	Exon 9 of 13	ENSP00000274813.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251198 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000103 AC: 15 AN: 1460998 Hom.: 0 Cov.: 30 AF XY: 0.0000124 AC XY: 9 AN XY: 726812

African (AFR) AF: 0.00 AC: 0 AN: 33432

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26090

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.0000135 AC: 15 AN: 1111310

Other (OTH) AF: 0.00 AC: 0 AN: 60352

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Methylmalonic aciduria due to methylmalonyl-CoA mutase deficiency Pathogenic:1

University Children's Hospital, University of Zurich

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.72
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Pathogenic	0.14
CADD	Pathogenic	27
DANN	Uncertain	1.0
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.36	D
MetaRNN	Pathogenic	0.86	D
MetaSVM	Pathogenic	1.0	D
PhyloP100		8.6
PrimateAI	Uncertain	0.77	T
PROVEAN	Uncertain	-3.6	D
REVEL	Pathogenic	0.76
Sift	Uncertain	0.0030	D
Sift4G	Benign	0.061	T
Vest4		0.75
MutPred		0.56		Loss of catalytic residue at A552 (P = 0.0624)
MVP		0.98
MPC		0.38
ClinPred		0.97	D
GERP RS		4.4
gMVP		0.72
Mutation Taster		=9/91	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

Other links and lift over

dbSNP: rs879253845; hg19: chr6-49412373;