rs146833395

Variant names:

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_004614.5(TK2):c.539-20A>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00147 in 1,609,722 control chromosomes in the GnomAD database, including 28 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.0075 ( 8 hom., cov: 32)

Exomes 𝑓: 0.00084 ( 20 hom. )

Consequence

TK2
NM_004614.5 intron

Scores

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: -0.0670

Publications

0 publications found

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 Gene-Disease associations (from GenCC):

mitochondrial disease
Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
mitochondrial DNA depletion syndrome, myopathic form
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)
autosomal recessive progressive external ophthalmoplegia
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

TK2 links:

ENSG00000260851 (HGNC:):

ENSG00000260851 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -20 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.86).

BP6

Variant 16-66517235-T-C is Benign according to our data. Variant chr16-66517235-T-C is described in ClinVar as Benign. ClinVar VariationId is 137662.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS1

Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00752 (1145/152290) while in subpopulation AFR AF = 0.0258 (1073/41542). AF 95% confidence interval is 0.0245. There are 8 homozygotes in GnomAd4. There are 520 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

BS2

High Homozygotes in GnomAd4 at 8 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TK2	NM_004614.5 link	c.539-20A>G		intron_variant	Intron 7 of 9	ENST00000544898.6	NP_004605.4	O00142-1Q8IZR3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TK2	ENST00000544898.6 link	c.539-20A>G		intron_variant	Intron 7 of 9	1	NM_004614.5	ENSP00000440898.2		O00142-1
ENSG00000260851	ENST00000561728.1 link	n.-34A>G		upstream_gene_variant		2		ENSP00000462196.1		J3KRW8

Frequencies

GnomAD3 genomes

AF:

0.00750

AC:

1142

AN:

152172

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0258

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00340

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00316

Gnomad NFE

AF:

0.000147

Gnomad OTH

AF:

0.00431

GnomAD2 exomes

AF:

0.00191

AC:

480

AN:

251458

AF XY:

0.00150

show subpopulations

Gnomad AFR exome

AF:

0.0255

Gnomad AMR exome

AF:

0.00119

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000114

Gnomad OTH exome

AF:

0.000978

GnomAD4 exome

AF:

0.000836

AC:

1219

AN:

1457432

Hom.:

Cov.:

AF XY:

0.000724

AC XY:

525

AN XY:

725374

show subpopulations

African (AFR)

AF:

0.0275

AC:

920

AN:

33396

American (AMR)

AF:

0.00139

AC:

AN:

44720

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26108

East Asian (EAS)

AF:

0.00

AC:

AN:

39668

South Asian (SAS)

AF:

0.0000929

AC:

AN:

86154

European-Finnish (FIN)

AF:

0.0000375

AC:

AN:

53400

Middle Eastern (MID)

AF:

0.00243

AC:

AN:

5760

European-Non Finnish (NFE)

AF:

0.0000677

AC:

AN:

1107986

Other (OTH)

AF:

0.00229

AC:

138

AN:

60240

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.500

Heterozygous variant carriers

131

197

262

328

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Exome Hom

Variant carriers

128

160

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.00752

AC:

1145

AN:

152290

Hom.:

Cov.:

AF XY:

0.00698

AC XY:

520

AN XY:

74478

show subpopulations

African (AFR)

AF:

0.0258

AC:

1073

AN:

41542

American (AMR)

AF:

0.00340

AC:

AN:

15300

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5190

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10614

Middle Eastern (MID)

AF:

0.00340

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.000147

AC:

AN:

68026

Other (OTH)

AF:

0.00426

AC:

AN:

2112

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.503

Heterozygous variant carriers

111

166

222

277

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Genome Hom

Variant carriers

100

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.00463

Hom.:

Bravo

AF:

0.00923

Asia WGS

AF:

0.00115

AC:

AN:

3478

ClinVar

Significance: Benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:2

PreventionGenetics, part of Exact Sciences

Significance:Benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Jul 11, 2011

GeneDx

Significance:Benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

not provided

Benign:2

Breakthrough Genomics, Breakthrough Genomics

Significance:Benign

Review Status:criteria provided, single submitter

Collection Method:not provided

- -

Feb 03, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.86

CADD

Benign

3.7

(source)

DANN

Benign

0.69

PhyloP100

-0.067

Mutation Taster

=100/0

polymorphism

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

Details are displayed if max score is > 0.2

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over