M-3252-A-T

Position:

• chrM-3252-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The ENST00000386347.1(MT-TL1):​n.23A>T variant causes a non coding transcript exon change. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Mitomap GenBank: Absent
• Consequence: MT-TL1 ENST00000386347.1 non_coding_transcript_exon
• Scores: Mitotip Uncertain 11
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1 MELAS,EXIT
• Conservation: PhyloP100: 6.99

Genes affected

MT-TL1 (HGNC:7490): (mitochondrially encoded tRNA leucine 1 (UUA/G)) Implicated in cardiomyopathy. [provided by Alliance of Genome Resources, Apr 2022]

TRNL1 (HGNC:):

MT-RNR2 (HGNC:7471): (mitochondrially encoded 16S RNA) Enables G protein-coupled receptor binding activity; protein self-association; and receptor antagonist activity. Involved in several processes, including leukocyte chemotaxis; negative regulation of cell death; and negative regulation of neuroinflammatory response. Located in several cellular components, including mitochondrion; perinuclear region of cytoplasm; and sperm midpiece. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: No frequency data in Mitomap. Probably very rare.
• BP4: Mitotip and hmtvar scores support benign criterium.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TRNL1	TRNL1.1	n.23A>T		non_coding_transcript_exon_variant	1/1
RNR2	RNR2.1			downstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MT-TL1	ENST00000386347.1	n.23A>T		non_coding_transcript_exon_variant	1/1
MT-RNR2	ENST00000387347.2			downstream_gene_variant

Frequencies

GnomAD4 exome Cov.: 0

We have no GnomAD4 genomes data on this position. Probably position not covered by the project.

Mitomap

MELAS,EXIT

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

MELAS syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine

Jul 12, 2019

The NC_012920.1:m.3252A>T variant in MT-TL1 gene is interpreted to be a Unknown Significance variant based on the modified ACMG guidelines (unpublished). This variant meets the following evidence codes reported in the guidelines: PM2, PM9, PP6 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
Mitotip	Uncertain	11
Hmtvar	Benign	0.15

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs199474661; hg19: chrM-3253;