Variant 16-66509847-G-A details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_004614.5(TK2):c.*2121C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000412 in 152,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00040 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0034 ( 0 hom. )

Consequence

TK2
NM_004614.5 3_prime_UTR

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -1.76

Variant links:

Genes affected

TK2 (HGNC:11831): (thymidine kinase 2) This gene encodes a deoxyribonucleoside kinase that specifically phosphorylates thymidine, deoxycytidine, and deoxyuridine. The encoded enzyme localizes to the mitochondria and is required for mitochondrial DNA synthesis. Mutations in this gene are associated with a myopathic form of mitochondrial DNA depletion syndrome. Alternate splicing results in multiple transcript variants encoding distinct isoforms, some of which lack transit peptide, so are not localized to mitochondria. [provided by RefSeq, Dec 2012]

TK2 links:

(HGNC:):

links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.9).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TK2	NM_004614.5 linkuse as main transcript	c.*2121C>T		3_prime_UTR_variant	10/10	ENST00000544898.6	NP_004605.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TK2	ENST00000544898.6 linkuse as main transcript	c.*2121C>T		3_prime_UTR_variant	10/10	1	NM_004614.5	ENSP00000440898	P1	O00142-1
	ENST00000568560.1 linkuse as main transcript	n.322-12G>A		splice_polypyrimidine_tract_variant, intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes

AF:

0.000401

AC:

AN:

152184

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000262

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000576

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.000848

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000559

Gnomad OTH

AF:

0.000955

GnomAD4 exome

AF:

0.00342

AC:

AN:

584

Hom.:

Cov.:

AF XY:

0.00474

AC XY:

AN XY:

422

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00463

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.000401

AC:

AN:

152302

Hom.:

Cov.:

AF XY:

0.000443

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.000120

Gnomad4 AMR

AF:

0.000262

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000578

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000848

Gnomad4 NFE

AF:

0.000559

Gnomad4 OTH

AF:

0.000945

Alfa

AF:

0.000414

Hom.:

Bravo

AF:

0.000427

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Mitochondrial DNA depletion syndrome, myopathic form

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.90

CADD

Benign

0.094

DANN

Benign

0.68

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over