chr1-45508812-G-A

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PP2PP3_Moderate

The NM_015506.3(MMACHC):​c.446G>A​(p.Cys149Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,916 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

MMACHC
NM_015506.3 missense

Scores

13
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.35

Publications

0 publications found
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]
MMACHC Gene-Disease associations (from GenCC):
  • methylmalonic aciduria and homocystinuria type cblC
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Myriad Women’s Health, ClinGen, G2P, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM1
In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 5 uncertain in NM_015506.3
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 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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.918

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_015506.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MMACHC
NM_015506.3
MANE Select
c.446G>Ap.Cys149Tyr
missense
Exon 4 of 4NP_056321.2
MMACHC
NM_001330540.2
c.275G>Ap.Cys92Tyr
missense
Exon 4 of 4NP_001317469.1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MMACHC
ENST00000401061.9
TSL:2 MANE Select
c.446G>Ap.Cys149Tyr
missense
Exon 4 of 4ENSP00000383840.4
MMACHC
ENST00000616135.1
TSL:2
c.275G>Ap.Cys92Tyr
missense
Exon 4 of 5ENSP00000478859.1
MMACHC
ENST00000933807.1
c.251G>Ap.Cys84Tyr
missense
Exon 3 of 3ENSP00000603866.1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152190
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000402
AC:
1
AN:
249004
AF XY:
0.00000740
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461726
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727150
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44686
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26110
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86238
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111946
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152190
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74342
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

ClinVar submissions as Germline
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
Cobalamin C disease (2)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.56
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.89
D
Eigen
Pathogenic
0.89
Eigen_PC
Pathogenic
0.86
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.92
D
M_CAP
Pathogenic
0.59
D
MetaRNN
Pathogenic
0.92
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.2
M
PhyloP100
9.4
PrimateAI
Uncertain
0.73
T
PROVEAN
Pathogenic
-7.6
D
REVEL
Pathogenic
0.94
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.0020
D
Polyphen
0.98
D
Vest4
0.88
MutPred
0.62
Gain of MoRF binding (P = 0.0739)
MVP
0.97
MPC
0.073
ClinPred
0.99
D
GERP RS
5.6
Varity_R
0.96
gMVP
0.98
Mutation Taster
=14/86
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.050
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: rs1161394470; hg19: chr1-45974484; API