5-7878079-T-G

Variant names:

• chr5-7878079-T-G
• rs161870
• NM_002454.3:c.537T>G

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_002454.3(MTRR):​c.537T>G​(p.Leu179Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L179L) has been classified as Benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MTRR NM_002454.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -3.79
• Publications: 23 publications found

Genes affected

MTRR (HGNC:7473): (5-methyltetrahydrofolate-homocysteine methyltransferase reductase) This gene encodes a member of the ferredoxin-NADP(+) reductase (FNR) family of electron transferases. This protein functions in the synthesis of methionine by regenerating methionine synthase to a functional state. Because methionine synthesis requires methyl-group transfer by a folate donor, activity of the encoded enzyme is important for folate metabolism and cellular methylation. Mutations in this gene can cause homocystinuria-megaloblastic anemia, cbl E type. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Dec 2015]

MTRR Gene-Disease associations (from GenCC):

• methylcobalamin deficiency type cblE

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

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.006).
• BP7: Synonymous conserved (PhyloP=-3.79 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002454.3. 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
	MTRR	NM_002454.3	MANE Select	c.537T>G	p.Leu179Leu	synonymous	Exon 5 of 15	NP_002445.2
	MTRR	NM_001364440.2		c.537T>G	p.Leu179Leu	synonymous	Exon 5 of 15	NP_001351369.1
	MTRR	NM_001364441.2		c.537T>G	p.Leu179Leu	synonymous	Exon 5 of 15	NP_001351370.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MTRR	ENST00000440940.7	TSL:1 MANE Select	c.537T>G	p.Leu179Leu	synonymous	Exon 5 of 15	ENSP00000402510.2
	MTRR	ENST00000264668.6	TSL:1	c.618T>G	p.Leu206Leu	synonymous	Exon 5 of 15	ENSP00000264668.2
	MTRR	ENST00000513439.5	TSL:1	n.*244T>G		non_coding_transcript_exon	Exon 5 of 15	ENSP00000426710.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.86
CADD	Benign	0.11
DANN	Benign	0.50
PhyloP100		-3.8

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: rs161870; hg19: chr5-7878192;