rs1554158777

Positions:

• chr6-49440318-G-A
• chr6-49440318-G-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PS1_Moderate PM1 PM2 PM5 PP3_Moderate PP5_Moderate

The NM_000255.4(MMUT):​c.1844C>T​(p.Pro615Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,740 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 (★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin UniProt. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P615T) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MMUT NM_000255.4 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.76

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]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PS1: Transcript NM_000255.4 (MMUT) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in UniProt
• 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
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.893
• PP5: Variant 6-49440318-G-A is Pathogenic according to our data. Variant chr6-49440318-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 1459268.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MMUT	NM_000255.4	c.1844C>T	p.Pro615Leu	missense_variant	11/13	ENST00000274813.4	NP_000246.2
MMUT	XM_005249143.4	c.1844C>T	p.Pro615Leu	missense_variant	11/13		XP_005249200.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MMUT	ENST00000274813.4	c.1844C>T	p.Pro615Leu	missense_variant	11/13	1	NM_000255.4	ENSP00000274813.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461740 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727180

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 22, 2021

This missense change has been observed in individuals with methylmalonic aciduria (PMID: 16435223, 22727635, 27167370). For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects MUT function (PMID: 25125334). 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. This variant is not present in population databases (ExAC no frequency). This sequence change replaces proline with leucine at codon 615 of the MUT protein (p.Pro615Leu). The proline residue is highly conserved and there is a moderate physicochemical difference between proline and leucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.84
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	31
DANN	Uncertain	1.0
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.97	D
M_CAP	Uncertain	0.21	D
MetaRNN	Pathogenic	0.89	D
MetaSVM	Pathogenic	0.92	D
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-9.8	D
REVEL	Pathogenic	0.87
Sift	Uncertain	0.013	D
Sift4G	Pathogenic	0.0	D
Vest4		0.84
MutPred		0.58		Loss of glycosylation at P615 (P = 0.0184);
MVP		0.99
MPC		0.33
ClinPred		1.0	D
GERP RS		4.8
gMVP		0.91

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr6-49408031;