rs765547005

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1PP3_ModeratePP5

The NM_052845.4(MMAB):​c.656A>G​(p.Tyr219Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000993 in 1,611,266 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

MMAB
NM_052845.4 missense

Scores

7
9
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:4O:1

Conservation

PhyloP100: 3.09

Publications

2 publications found
Variant links:
Genes affected
MMAB (HGNC:19331): (metabolism of cobalamin associated B) This gene encodes a protein that catalyzes the final step in the conversion of vitamin B(12) into adenosylcobalamin (AdoCbl), a vitamin B12-containing coenzyme for methylmalonyl-CoA mutase. Mutations in the gene are the cause of vitamin B12-dependent methylmalonic aciduria linked to the cblB complementation group. Alternatively spliced transcript variants have been found. [provided by RefSeq, Apr 2011]
MMAB Gene-Disease associations (from GenCC):
  • methylmalonic aciduria, cblB type
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, G2P, Myriad Women’s Health, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

PM1
In a chain Corrinoid adenosyltransferase MMAB (size 217) in uniprot entity MMAB_HUMAN there are 29 pathogenic changes around while only 7 benign (81%) in NM_052845.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.894
PP5
Variant 12-109557125-T-C is Pathogenic according to our data. Variant chr12-109557125-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 219007.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_052845.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MMAB
NM_052845.4
MANE Select
c.656A>Gp.Tyr219Cys
missense
Exon 9 of 9NP_443077.1
MMAB
NR_038118.2
n.767A>G
non_coding_transcript_exon
Exon 10 of 10

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
MMAB
ENST00000545712.7
TSL:1 MANE Select
c.656A>Gp.Tyr219Cys
missense
Exon 9 of 9ENSP00000445920.1
MMAB
ENST00000878519.1
c.719A>Gp.Tyr240Cys
missense
Exon 10 of 10ENSP00000548578.1
MMAB
ENST00000878520.1
c.596A>Gp.Tyr199Cys
missense
Exon 8 of 8ENSP00000548579.1

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152246
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000169
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:
0.0000239
AC:
6
AN:
251446
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.000369
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:
0.00000617
AC:
9
AN:
1458902
Hom.:
0
Cov.:
31
AF XY:
0.00000689
AC XY:
5
AN XY:
726050
show subpopulations
African (AFR)
AF:
0.000239
AC:
8
AN:
33438
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86210
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
9.01e-7
AC:
1
AN:
1109268
Other (OTH)
AF:
0.00
AC:
0
AN:
60292
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000459
AC:
7
AN:
152364
Hom.:
0
Cov.:
34
AF XY:
0.0000537
AC XY:
4
AN XY:
74510
show subpopulations
African (AFR)
AF:
0.000168
AC:
7
AN:
41596
American (AMR)
AF:
0.00
AC:
0
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
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: 0.489
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000739
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.0000330
AC:
4
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

ClinVar submissions as Germline
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
1
2
-
Methylmalonic aciduria, cblB type (4)
-
1
-
not provided (1)
-
1
-
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.30
BayesDel_addAF
Pathogenic
0.24
D
BayesDel_noAF
Pathogenic
0.42
CADD
Uncertain
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.64
D
Eigen
Uncertain
0.47
Eigen_PC
Uncertain
0.43
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Uncertain
0.93
D
M_CAP
Pathogenic
0.47
D
MetaRNN
Pathogenic
0.89
D
MetaSVM
Pathogenic
0.97
D
MutationAssessor
Uncertain
2.3
M
PhyloP100
3.1
PrimateAI
Uncertain
0.70
T
PROVEAN
Pathogenic
-5.4
D
REVEL
Pathogenic
0.91
Sift
Benign
0.032
D
Sift4G
Uncertain
0.057
T
Polyphen
0.99
D
Vest4
0.68
MVP
0.99
MPC
0.78
ClinPred
0.78
D
GERP RS
5.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.86
gMVP
0.93
Mutation Taster
=6/94
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs765547005; hg19: chr12-109994930; COSMIC: COSV57170130; COSMIC: COSV57170130; API