rs864309726

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_172250.3(MMAA):​c.266T>C​(p.Leu89Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,614,088 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. L89V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

MMAA
NM_172250.3 missense

Scores

12
5
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5O:1

Conservation

PhyloP100: 7.49

Publications

3 publications found
Variant links:
Genes affected
MMAA (HGNC:18871): (metabolism of cobalamin associated A) The protein encoded by this gene is involved in the translocation of cobalamin into the mitochondrion, where it is used in the final steps of adenosylcobalamin synthesis. Adenosylcobalamin is a coenzyme required for the activity of methylmalonyl-CoA mutase. Defects in this gene are a cause of methylmalonic aciduria. [provided by RefSeq, Jul 2008]
MMAA Gene-Disease associations (from GenCC):
  • methylmalonic aciduria, cblA type
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Myriad Women’s Health, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet, G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 14 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.97
PP5
Variant 4-145639405-T-C is Pathogenic according to our data. Variant chr4-145639405-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 218971.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
MMAANM_172250.3 linkc.266T>C p.Leu89Pro missense_variant Exon 2 of 7 ENST00000649156.2 NP_758454.1 Q8IVH4
MMAANM_001375644.1 linkc.266T>C p.Leu89Pro missense_variant Exon 2 of 7 NP_001362573.1
MMAAXM_011531684.4 linkc.266T>C p.Leu89Pro missense_variant Exon 2 of 7 XP_011529986.1 Q8IVH4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MMAAENST00000649156.2 linkc.266T>C p.Leu89Pro missense_variant Exon 2 of 7 NM_172250.3 ENSP00000497008.1 Q8IVH4

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152214
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251246
AF XY:
0.00
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:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461874
Hom.:
0
Cov.:
32
AF XY:
0.00000825
AC XY:
6
AN XY:
727232
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:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53412
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000809
AC:
9
AN:
1112008
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.515
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000197
AC:
3
AN:
152214
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41456
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
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:
0.0000441
AC:
3
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.608
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:
0.0000282
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Methylmalonic aciduria, cblA type Pathogenic:5Other:1
Mar 19, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 04, 2018
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. -

Aug 21, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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) performed at Invitae indicates that this missense variant is expected to disrupt MMAA protein function. Experimental studies have shown that this missense change affects MMAA function (PMID: 28497574). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. ClinVar contains an entry for this variant (Variation ID: 218971). This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 89 of the MMAA protein (p.Leu89Pro). This variant is present in population databases (no rsID available, gnomAD 0.002%). This missense change has been observed in individuals with cobalamin A type methylmalonic aciduria (PMID: 15523652, 34915869). -

-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Jun 15, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 07, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.92
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.46
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.63
D;.;D;D;D;D
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.75
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Benign
0.84
.;T;.;.;T;T
M_CAP
Pathogenic
0.40
D
MetaRNN
Pathogenic
0.97
D;D;D;D;D;D
MetaSVM
Pathogenic
0.90
D
MutationAssessor
Uncertain
2.8
M;.;M;M;M;.
PhyloP100
7.5
PrimateAI
Uncertain
0.68
T
PROVEAN
Uncertain
-4.1
.;.;D;.;.;D
REVEL
Pathogenic
0.95
Sift
Uncertain
0.0010
.;.;D;.;.;T
Sift4G
Pathogenic
0.0010
.;.;D;.;.;D
Polyphen
1.0
D;.;D;D;D;.
Vest4
0.92, 0.92
MutPred
0.89
Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);Loss of stability (P = 0.0012);
MVP
0.95
MPC
0.68
ClinPred
1.0
D
GERP RS
5.4
Varity_R
0.94
gMVP
0.95
Mutation Taster
=181/119
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: rs864309726; hg19: chr4-146560557; COSMIC: COSV55579924; COSMIC: COSV55579924; API