chr1-45508830-G-A

Position:

• chr1-45508830-G-A

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_015506.3(MMACHC):​c.464G>A​(p.Gly155Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G155R) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MMACHC NM_015506.3 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.36

Genes affected

MMACHC (HGNC:24525): (metabolism of cobalamin associated C) The exact function of the protein encoded by this gene is not known, however, its C-terminal region shows similarity to TonB, a bacterial protein involved in energy transduction for cobalamin (vitamin B12) uptake. Hence, it is postulated that this protein may have a role in the binding and intracellular trafficking of cobalamin. Mutations in this gene are associated with methylmalonic aciduria and homocystinuria type cblC. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 6 uncertain in NM_015506.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-45508829-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2202759.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989
• PP5: Variant 1-45508830-G-A is Pathogenic according to our data. Variant chr1-45508830-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 161119.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MMACHC	NM_015506.3	c.464G>A	p.Gly155Glu	missense_variant	4/4	ENST00000401061.9	NP_056321.2
MMACHC	NM_001330540.2	c.293G>A	p.Gly98Glu	missense_variant	4/4		NP_001317469.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MMACHC	ENST00000401061.9	c.464G>A	p.Gly155Glu	missense_variant	4/4	2	NM_015506.3	ENSP00000383840.4
MMACHC	ENST00000616135.1	c.293G>A	p.Gly98Glu	missense_variant	4/5	2		ENSP00000478859.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Cobalamin C disease Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Aug 01, 2013

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	D;T
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.91	D;D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	M;.
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-7.2	D;.
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0030	D;.
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.93
MutPred		0.87		Loss of MoRF binding (P = 0.0618);.;
MVP		0.98
MPC		0.080
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.93
gMVP		0.98

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

Other links and lift over

dbSNP: rs606231425; hg19: chr1-45974502;