Variant 2-149570069-G-A details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The NM_015702.3(MMADHC):c.796C>T(p.Arg266Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000093 in 1,613,418 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 Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

MMADHC
NM_015702.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.83

Variant links:

Genes affected

MMADHC (HGNC:25221): (metabolism of cobalamin associated D) This gene encodes a mitochondrial protein that is involved in an early step of vitamin B12 metabolism. Vitamin B12 (cobalamin) is essential for normal development and survival in humans. Mutations in this gene cause methylmalonic aciduria and homocystinuria type cblD (MMADHC), a disorder of cobalamin metabolism that is characterized by decreased levels of the coenzymes adenosylcobalamin and methylcobalamin. Pseudogenes have been identified on chromosomes 11 and X.[provided by RefSeq, Nov 2008]

MMADHC links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a mutagenesis_site Mildly decreases methylcobalamin levels and strongly increases adenosylcobalamin levels. (size 0) in uniprot entity MMAD_HUMAN

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.901

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MMADHC	NM_015702.3 link	c.796C>T	p.Arg266Cys	missense_variant	8/8	ENST00000303319.10	NP_056517.1	Q9H3L0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
MMADHC	ENST00000303319.10 link	c.796C>T	p.Arg266Cys	missense_variant	8/8	1	NM_015702.3	ENSP00000301920.5	Q9H3L0
MMADHC	ENST00000422782.2 link	c.898C>T	p.Arg300Cys	missense_variant	9/9	5		ENSP00000408331.2	F8WEC0
MMADHC	ENST00000428879.5 link	c.796C>T	p.Arg266Cys	missense_variant	7/7	2		ENSP00000389060.1	Q9H3L0

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152064

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000725

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000796

AC:

AN:

251346

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135852

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:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000684

AC:

AN:

1461354

Hom.:

Cov.:

AF XY:

0.0000110

AC XY:

AN XY:

726994

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:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000810

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152064

Hom.:

Cov.:

AF XY:

0.0000404

AC XY:

AN XY:

74262

show subpopulations

Gnomad4 AFR

AF:

0.0000725

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000189

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 19, 2024

The c.796C>T (p.R266C) alteration is located in exon 8 (coding exon 7) of the MMADHC gene. This alteration results from a C to T substitution at nucleotide position 796, causing the arginine (R) at amino acid position 266 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.13

BayesDel_addAF

Pathogenic

0.43

BayesDel_noAF

Pathogenic

0.39

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.72

D;D;D

Eigen

Pathogenic

0.86

Eigen_PC

Pathogenic

0.81

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.92

.;D;D

M_CAP

Benign

0.083

MetaRNN

Pathogenic

0.90

D;D;D

MetaSVM

Uncertain

0.74

MutationAssessor

Uncertain

2.9

M;M;.

PrimateAI

Pathogenic

0.86

PROVEAN

Uncertain

-3.6

D;D;D

REVEL

Pathogenic

0.87

Sift

Uncertain

0.0060

D;D;D

Sift4G

Benign

0.069

T;T;T

Polyphen

1.0

D;D;D

Vest4

0.80

MutPred

0.76

.;.;Loss of ubiquitination at K297 (P = 0.1179);

MVP

0.85

MPC

0.28

ClinPred

1.0

GERP RS

5.0

Varity_R

0.69

gMVP

0.65

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over