4-145639434-G-A

Variant names:

• chr4-145639434-G-A
• rs1553957915
• NM_172250.3:c.295G>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_172250.3(MMAA):​c.295G>A​(p.Ala99Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MMAA NM_172250.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.64
• Publications: 0 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_172250.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MMAA	NM_172250.3	MANE Select	c.295G>A	p.Ala99Thr	missense	Exon 2 of 7	NP_758454.1
	MMAA	NM_001375644.1		c.295G>A	p.Ala99Thr	missense	Exon 2 of 7	NP_001362573.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MMAA	ENST00000649156.2	MANE Select	c.295G>A	p.Ala99Thr	missense	Exon 2 of 7	ENSP00000497008.1
	MMAA	ENST00000511969.4	TSL:1	n.295G>A		non_coding_transcript_exon	Exon 1 of 5	ENSP00000427422.1
	MMAA	ENST00000541599.5	TSL:5	c.295G>A	p.Ala99Thr	missense	Exon 2 of 7	ENSP00000442284.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Methylmalonic aciduria, cblA type Uncertain:1

Dec 03, 2017

Genomic Research Center, Shahid Beheshti University of Medical Sciences

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.24	T
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Benign	0.081	D
MetaRNN	Uncertain	0.63	D
MetaSVM	Uncertain	0.39	D
MutationAssessor	Uncertain	2.8	M
PhyloP100		7.6
PrimateAI	Uncertain	0.50	T
PROVEAN	Benign	-1.6	N
REVEL	Uncertain	0.56
Sift	Benign	0.11	T
Sift4G	Benign	0.20	T
Polyphen		0.88	P
Vest4		0.69
MutPred		0.39		Gain of phosphorylation at A99 (P = 0.1959)
MVP		0.67
MPC		0.13
ClinPred		0.97	D
GERP RS		4.6
Varity_R		0.48
gMVP		0.43
Mutation Taster		=192/108	polymorphism

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

Other links and lift over

dbSNP: rs1553957915; hg19: chr4-146560586;