12-109554349-C-G

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_StrongBS1_SupportingBS2

The NM_052845.4(MMAB):​c.*2679G>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000493 in 454,094 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00068 ( 2 hom. )

Consequence

MMAB
NM_052845.4 3_prime_UTR

Scores

2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.261
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -9 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.83).
BS1
Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000131 (20/152290) while in subpopulation SAS AF= 0.0029 (14/4830). AF 95% confidence interval is 0.00175. There are 0 homozygotes in gnomad4. There are 12 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
MMABNM_052845.4 linkuse as main transcriptc.*2679G>C 3_prime_UTR_variant 9/9 ENST00000545712.7 NP_443077.1 Q96EY8

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
MMABENST00000545712 linkuse as main transcriptc.*2679G>C 3_prime_UTR_variant 9/91 NM_052845.4 ENSP00000445920.1 Q96EY8

Frequencies

GnomAD3 genomes
AF:
0.000131
AC:
20
AN:
152172
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:
0.00290
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000621
AC:
81
AN:
130490
Hom.:
1
AF XY:
0.000856
AC XY:
61
AN XY:
71228
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 SAS exome
AF:
0.00344
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000603
Gnomad OTH exome
AF:
0.000250
GnomAD4 exome
AF:
0.000676
AC:
204
AN:
301804
Hom.:
2
Cov.:
0
AF XY:
0.000977
AC XY:
168
AN XY:
172002
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00320
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000630
Gnomad4 OTH exome
AF:
0.000142
GnomAD4 genome
AF:
0.000131
AC:
20
AN:
152290
Hom.:
0
Cov.:
32
AF XY:
0.000161
AC XY:
12
AN XY:
74460
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00290
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000882
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000434
Hom.:
0
Bravo
AF:
0.0000416
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Methylmalonic aciduria, cblB type Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.83
CADD
Benign
2.9
DANN
Benign
0.49

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs546327751; hg19: chr12-109992154; API