M-9995-T-C

Position:

• chrM-9995-T-C

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4 BP6_Moderate BS2

The ENST00000387429.1(MT-TG):​n.5T>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: 6)
• Consequence: MT-TG ENST00000387429.1 non_coding_transcript_exon
• Scores: Mitotip Uncertain 9.6
• Clinical Significance: Likely benign criteria provided, single submitter B:1 No linked disesase in Mitomap
• Conservation: PhyloP100: 0.680

Genes affected

MT-TG (HGNC:7486): (mitochondrially encoded tRNA glycine)

TRNG (HGNC:):

MT-CO3 (HGNC:7422): (mitochondrially encoded cytochrome c oxidase III) Predicted to enable electron transfer activity and oxidoreduction-driven active transmembrane transporter activity. Involved in respiratory chain complex IV assembly. Part of respiratory chain complex IV. Implicated in MELAS syndrome. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Benign. Variant got -7 ACMG points.

• BP4: Mitotip and hmtvar scores support benign criterium.
• BP6: Variant M-9995-T-C is Benign according to our data. Variant chrM-9995-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 690088.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS2: High AC in GnomadMitoHomoplasmic at 4

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TRNG	TRNG.1	n.5T>C		non_coding_transcript_exon_variant	1/1
COX3	COX3.1			downstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MT-TG	ENST00000387429.1	n.5T>C		non_coding_transcript_exon_variant	1/1
MT-CO3	ENST00000362079.2			downstream_gene_variant				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: 6

Gnomad homoplasmic AF: 0.000071 AC: 4 AN: 56432

Gnomad heteroplasmic AF: 0.000018 AC: 1 AN: 56432

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.9995T>C variant in MT-TG 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: BS1, BP4, BP6 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
Mitotip	Uncertain	9.6
Hmtvar	Benign	0.20

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1603222616; hg19: chrM-9996;