rs72650187

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_052845.4(MMAB):​c.349-17T>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00808 in 1,593,234 control chromosomes in the GnomAD database, including 68 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0056 ( 2 hom., cov: 32)
Exomes 𝑓: 0.0083 ( 66 hom. )

Consequence

MMAB
NM_052845.4 intron

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 0.557

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: Benign. The variant received -20 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.88).
BP6
Variant 12-109561869-A-G is Benign according to our data. Variant chr12-109561869-A-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 445771.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00561 (855/152298) while in subpopulation NFE AF = 0.00972 (661/68018). AF 95% confidence interval is 0.0091. There are 2 homozygotes in GnomAd4. There are 381 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 2 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MMABNM_052845.4 linkc.349-17T>C intron_variant Intron 4 of 8 ENST00000545712.7 NP_443077.1 Q96EY8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMABENST00000545712.7 linkc.349-17T>C intron_variant Intron 4 of 8 1 NM_052845.4 ENSP00000445920.1 Q96EY8

Frequencies

GnomAD3 genomes
AF:
0.00562
AC:
856
AN:
152180
Hom.:
2
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00181
Gnomad AMI
AF:
0.00219
Gnomad AMR
AF:
0.00183
Gnomad ASJ
AF:
0.00115
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00249
Gnomad FIN
AF:
0.00649
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00972
Gnomad OTH
AF:
0.00239
GnomAD2 exomes
AF:
0.00579
AC:
1240
AN:
214260
AF XY:
0.00599
show subpopulations
Gnomad AFR exome
AF:
0.00140
Gnomad AMR exome
AF:
0.00107
Gnomad ASJ exome
AF:
0.000746
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00845
Gnomad NFE exome
AF:
0.00959
Gnomad OTH exome
AF:
0.00547
GnomAD4 exome
AF:
0.00834
AC:
12017
AN:
1440936
Hom.:
66
Cov.:
32
AF XY:
0.00819
AC XY:
5854
AN XY:
715020
show subpopulations
African (AFR)
AF:
0.00130
AC:
43
AN:
33018
American (AMR)
AF:
0.00131
AC:
56
AN:
42664
Ashkenazi Jewish (ASJ)
AF:
0.000777
AC:
20
AN:
25748
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38886
South Asian (SAS)
AF:
0.00385
AC:
321
AN:
83482
European-Finnish (FIN)
AF:
0.00965
AC:
497
AN:
51494
Middle Eastern (MID)
AF:
0.00191
AC:
11
AN:
5750
European-Non Finnish (NFE)
AF:
0.00971
AC:
10683
AN:
1100354
Other (OTH)
AF:
0.00648
AC:
386
AN:
59540
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
599
1198
1798
2397
2996
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
404
808
1212
1616
2020
<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:
0.00561
AC:
855
AN:
152298
Hom.:
2
Cov.:
32
AF XY:
0.00512
AC XY:
381
AN XY:
74478
show subpopulations
African (AFR)
AF:
0.00180
AC:
75
AN:
41564
American (AMR)
AF:
0.00183
AC:
28
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00115
AC:
4
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00228
AC:
11
AN:
4820
European-Finnish (FIN)
AF:
0.00649
AC:
69
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00972
AC:
661
AN:
68018
Other (OTH)
AF:
0.00237
AC:
5
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
47
93
140
186
233
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.00717
Hom.:
4
Bravo
AF:
0.00496
Asia WGS
AF:
0.00231
AC:
8
AN:
3478

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:2
Aug 03, 2017
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

not specified Benign:1
Nov 29, 2017
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Methylmalonic aciduria, cblB type Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.88
CADD
Benign
11
DANN
Benign
0.31
PhyloP100
0.56
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs72650187; hg19: chr12-109999674; API