1-45500372-G-A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 3P and 5B. PM1PP2BP4_StrongBP6

The NM_015506.3(MMACHC):​c.40G>A​(p.Asp14Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000105 in 1,614,186 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. D14D) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 1 hom. )

Consequence

MMACHC
NM_015506.3 missense

Scores

3
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:2

Conservation

PhyloP100: 1.89
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM1
In a chain Cyanocobalamin reductase / alkylcobalamin dealkylase (size 281) in uniprot entity MMAC_HUMAN there are 56 pathogenic changes around while only 15 benign (79%) in NM_015506.3
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 28 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Gene score misZ: -1.0759 (below the threshold of 3.09). Trascript score misZ: -0.13772 (below the threshold of 3.09). GenCC associations: The gene is linked to methylmalonic aciduria and homocystinuria type cblC.
BP4
Computational evidence support a benign effect (MetaRNN=0.008714229).
BP6
Variant 1-45500372-G-A is Benign according to our data. Variant chr1-45500372-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 582169.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=1, Likely_benign=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMACHCNM_015506.3 linkc.40G>A p.Asp14Asn missense_variant Exon 1 of 4 ENST00000401061.9 NP_056321.2 Q9Y4U1
MMACHCNM_001330540.2 linkc.-183G>A 5_prime_UTR_variant Exon 1 of 4 NP_001317469.1 Q9Y4U1A0A0C4DGU2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMACHCENST00000401061.9 linkc.40G>A p.Asp14Asn missense_variant Exon 1 of 4 2 NM_015506.3 ENSP00000383840.4 Q9Y4U1
MMACHCENST00000616135.1 linkc.-132G>A 5_prime_UTR_variant Exon 1 of 5 2 ENSP00000478859.1 A0A0C4DGU2

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152216
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000232
AC:
58
AN:
249576
AF XY:
0.000310
show subpopulations
Gnomad AFR exome
AF:
0.0000645
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000108
AC:
158
AN:
1461852
Hom.:
1
Cov.:
30
AF XY:
0.000140
AC XY:
102
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00168
AC:
145
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5746
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1112010
Other (OTH)
AF:
0.000149
AC:
9
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
12
25
37
50
62
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000722
AC:
11
AN:
152334
Hom.:
0
Cov.:
32
AF XY:
0.000107
AC XY:
8
AN XY:
74488
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41574
American (AMR)
AF:
0.00
AC:
0
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00207
AC:
10
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.539
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.000281
AC:
34
Asia WGS
AF:
0.00115
AC:
4
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Cobalamin C disease Uncertain:1Benign:1
Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 30, 2021
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

MMACHC-related disorder Benign:1
May 01, 2023
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.092
BayesDel_addAF
Benign
-0.32
T
BayesDel_noAF
Benign
-0.24
CADD
Benign
21
DANN
Uncertain
1.0
DEOGEN2
Benign
0.082
T
Eigen
Benign
0.013
Eigen_PC
Benign
0.16
FATHMM_MKL
Benign
0.63
D
LIST_S2
Benign
0.81
T
M_CAP
Benign
0.056
D
MetaRNN
Benign
0.0087
T
MetaSVM
Uncertain
0.46
D
MutationAssessor
Benign
1.2
L
PhyloP100
1.9
PrimateAI
Uncertain
0.58
T
PROVEAN
Benign
-0.54
N
REVEL
Benign
0.24
Sift
Benign
0.14
T
Sift4G
Benign
0.15
T
Polyphen
0.34
B
Vest4
0.18
MutPred
0.22
Gain of methylation at K11 (P = 0.1);
MVP
0.96
MPC
0.012
ClinPred
0.13
T
GERP RS
3.8
PromoterAI
-0.025
Neutral
Varity_R
0.26
gMVP
0.35
Mutation Taster
=91/9
polymorphism

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

Other links and lift over

dbSNP: rs563710045; hg19: chr1-45966044; API