M-8300-T-C

Position:

• chrM-8300-T-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 0P and 3B. BP4 BP6_Moderate

The ENST00000387421.1(MT-TK):​n.6T>C variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. Variant has been reported in ClinVar as Likely benign (★).

• Frequency: Mitomap GenBank: 𝑓 0.00010 (AC: 5)
• Consequence: MT-TK ENST00000387421.1 non_coding_transcript_exon
• Scores: Mitotip Uncertain 9.2
• Clinical Significance: Likely benign criteria provided, single submitter B:1 No linked disesase in Mitomap
• Conservation: PhyloP100: 2.39

Genes affected

MT-TK (HGNC:7489): (mitochondrially encoded tRNA lysine)

TRNK (HGNC:):

MT-CO2 (HGNC:7421): (mitochondrially encoded cytochrome c oxidase II) Contributes to cytochrome-c oxidase activity. Predicted to be involved in mitochondrial electron transport, cytochrome c to oxygen and positive regulation of vasoconstriction. Located in mitochondrial inner membrane. Part of respiratory chain complex IV. Biomarker of Huntington's disease and stomach cancer. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• BP4: Mitotip and hmtvar scores support benign criterium.
• BP6: Variant M-8300-T-C is Benign according to our data. Variant chrM-8300-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 690064.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TRNK	TRNK.1	n.6T>C		non_coding_transcript_exon_variant	1/1
COX2	COX2.1			downstream_gene_variant			YP_003024029.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MT-TK	ENST00000387421.1	n.6T>C		non_coding_transcript_exon_variant	1/1
MT-CO2	ENST00000361739.1			downstream_gene_variant				ENSP00000354876	P1

Frequencies

GnomAD4 exome Cov.: 0

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

Mitomap GenBank AF: 0.00010 AC: 5

Gnomad homoplasmic AF: 0.000035 AC: 2 AN: 56431

Gnomad heteroplasmic AF: 0.0 AC: 0 AN: 56431

Mitomap

No disease associated.

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Juvenile myopathy, encephalopathy, lactic acidosis AND stroke Benign:1

Likely benign, 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.8300T>C variant in MT-TK gene is interpreted to be a Likely Benign variant based on the modified ACMG guidelines (unpublished). This variant meets the following evidence codes reported in the guidelines: BP4, BP5 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
Mitotip	Uncertain	9.2
Hmtvar	Benign	0.050

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1603221393; hg19: chrM-8301;