rs1553321372

Variant names:

• chr1-236859827-A-G
• rs1553321372
• NM_000254.3:c.1954-6A>G

Your query was ambiguous. Multiple possible variants found:

• chr1-236859827-A-G
• chr1-236859827-A-C
• chr1-236859827-A-T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000254.3(MTR):​c.1954-6A>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,612,894 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MTR NM_000254.3 splice_region, intron
• Scores: Splicing: ADA: 0.9462
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.0810
• Publications: 1 publications found

Genes affected

MTR (HGNC:7468): (5-methyltetrahydrofolate-homocysteine methyltransferase) This gene encodes the 5-methyltetrahydrofolate-homocysteine methyltransferase. This enzyme, also known as cobalamin-dependent methionine synthase, catalyzes the final step in methionine biosynthesis. Mutations in MTR have been identified as the underlying cause of methylcobalamin deficiency complementation group G. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, May 2014]

MTR Gene-Disease associations (from GenCC):

• methylcobalamin deficiency type cblG

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, G2P

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. Scorers claiming Benign: dbscSNV1_ADA.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000254.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MTR	NM_000254.3	MANE Select	c.1954-6A>G		splice_region intron	N/A	NP_000245.2	Q99707-1
	MTR	NM_001291939.1		c.1954-6A>G		splice_region intron	N/A	NP_001278868.1	Q99707-2
	MTR	NM_001410942.1		c.1954-6A>G		splice_region intron	N/A	NP_001397871.1	A0A7P0TAJ0

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MTR	ENST00000366577.10	TSL:1 MANE Select	c.1954-6A>G		splice_region intron	N/A	ENSP00000355536.5	Q99707-1
	MTR	ENST00000535889.6	TSL:1	c.1954-6A>G		splice_region intron	N/A	ENSP00000441845.1	Q99707-2
	MTR	ENST00000366576.3	TSL:1	c.616-6A>G		splice_region intron	N/A	ENSP00000355535.3	B1ANE3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152158 Hom.: 0 Cov.: 32

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460736 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726766

African (AFR) AF: 0.00 AC: 0 AN: 33464

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39672

South Asian (SAS) AF: 0.00 AC: 0 AN: 86240

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111022

Other (OTH) AF: 0.00 AC: 0 AN: 60356

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152158 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74338

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15280

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: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Methylcobalamin deficiency type cblG (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	21
DANN	Benign	0.52
PhyloP100		0.081

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.95
dbscSNV1_RF	Pathogenic	0.81
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		1.0		Position offset: 1
DS_AL_spliceai		0.52		Position offset: 6

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1553321372; hg19: chr1-237023127;