1-45508282-T-C

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM5PP2PP3_StrongPP5_Very_Strong

The NM_015506.3(MMACHC):​c.347T>C​(p.Leu116Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000217 in 1,614,056 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L116V) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

MMACHC
NM_015506.3 missense

Scores

13
4
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7O:1

Conservation

PhyloP100: 7.26

Publications

14 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: Pathogenic. The variant received 17 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 10 uncertain in NM_015506.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-45508281-C-G is described in CliVar as Likely_pathogenic. Clinvar id is 1525862.Status of the report is criteria_provided_single_submitter, 1 stars.
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, 0.973
PP5
Variant 1-45508282-T-C is Pathogenic according to our data. Variant chr1-45508282-T-C is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 1422.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-45508282-T-C is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 1422.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-45508282-T-C is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 1422.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-45508282-T-C is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 1422.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-45508282-T-C is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 1422.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMACHCNM_015506.3 linkc.347T>C p.Leu116Pro missense_variant Exon 3 of 4 ENST00000401061.9 NP_056321.2 Q9Y4U1
MMACHCNM_001330540.2 linkc.176T>C p.Leu59Pro missense_variant Exon 3 of 4 NP_001317469.1 Q9Y4U1A0A0C4DGU2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMACHCENST00000401061.9 linkc.347T>C p.Leu116Pro missense_variant Exon 3 of 4 2 NM_015506.3 ENSP00000383840.4 Q9Y4U1
MMACHCENST00000616135.1 linkc.176T>C p.Leu59Pro missense_variant Exon 3 of 5 2 ENSP00000478859.1 A0A0C4DGU2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152190
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000481
AC:
12
AN:
249442
AF XY:
0.0000887
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:
0.0000233
AC:
34
AN:
1461866
Hom.:
0
Cov.:
34
AF XY:
0.0000289
AC XY:
21
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
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:
39700
South Asian (SAS)
AF:
0.000359
AC:
31
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111990
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152190
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74356
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
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

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:
0.00000925
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000745
AC:
9

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cobalamin C disease Pathogenic:7
Feb 17, 2017
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Apr 11, 2023
Genome-Nilou Lab
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 08, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 116 of the MMACHC protein (p.Leu116Pro). This variant is present in population databases (rs121918240, gnomAD 0.04%). This missense change has been observed in individual(s) with homocystinuria, cblC type (PMID: 14568819, 16311595, 18245139, 20631720, 20924684; Invitae). ClinVar contains an entry for this variant (Variation ID: 1422). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on MMACHC protein function. For these reasons, this variant has been classified as Pathogenic. -

Apr 23, 2020
Neurology Department, Peking University First Hospital
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Jan 01, 2006
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Mar 25, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 20, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Disorders of Intracellular Cobalamin Metabolism Other:1
-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.92
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.56
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.90
D;T
Eigen
Pathogenic
0.85
Eigen_PC
Pathogenic
0.80
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Benign
0.84
T;D
M_CAP
Pathogenic
0.44
D
MetaRNN
Pathogenic
0.97
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
M;.
PhyloP100
7.3
PrimateAI
Uncertain
0.77
T
PROVEAN
Pathogenic
-6.9
D;.
REVEL
Pathogenic
0.97
Sift
Uncertain
0.0020
D;.
Sift4G
Pathogenic
0.0010
D;D
Polyphen
1.0
D;.
Vest4
0.98
MutPred
0.91
Gain of disorder (P = 0.0089);.;
MVP
0.97
MPC
0.080
ClinPred
0.91
D
GERP RS
5.8
Varity_R
0.98
gMVP
0.96
Mutation Taster
=5/95
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

Publications

Other links and lift over

dbSNP: rs121918240; hg19: chr1-45973954; API