rs529176585

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP6BS1

The NM_004614.5(TK2):​c.699+6_699+9delTAAG variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000118 in 1,612,932 control chromosomes in the GnomAD database, including 1 homozygotes. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00021 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 1 hom. )

Consequence

TK2
NM_004614.5 splice_region, intron

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:2

Conservation

PhyloP100: 2.28

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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP6
Variant 16-66513721-TCTTA-T is Benign according to our data. Variant chr16-66513721-TCTTA-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 225491.
BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.000211 (32/151954) while in subpopulation EAS AF = 0.00581 (30/5164). AF 95% confidence interval is 0.00418. There are 0 homozygotes in GnomAd4. There are 18 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TK2NM_004614.5 linkc.699+6_699+9delTAAG splice_region_variant, intron_variant Intron 9 of 9 ENST00000544898.6 NP_004605.4 O00142-1Q8IZR3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TK2ENST00000544898.6 linkc.699+6_699+9delTAAG splice_region_variant, intron_variant Intron 9 of 9 1 NM_004614.5 ENSP00000440898.2 O00142-1
ENSG00000260851ENST00000561728.1 linkn.147+6_147+9delTAAG splice_region_variant, intron_variant Intron 2 of 5 2 ENSP00000462196.1 J3KRW8

Frequencies

GnomAD3 genomes
AF:
0.000211
AC:
32
AN:
151836
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000656
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00580
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000613
AC:
154
AN:
251254
AF XY:
0.000633
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00821
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000109
AC:
159
AN:
1460978
Hom.:
1
AF XY:
0.000117
AC XY:
85
AN XY:
726850
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33454
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00365
AC:
145
AN:
39688
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86234
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53402
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5632
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111374
Other (OTH)
AF:
0.000133
AC:
8
AN:
60340
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.454
Heterozygous variant carriers
0
11
21
32
42
53
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
10
20
30
40
50
<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:
0.000211
AC:
32
AN:
151954
Hom.:
0
Cov.:
32
AF XY:
0.000242
AC XY:
18
AN XY:
74260
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41424
American (AMR)
AF:
0.0000655
AC:
1
AN:
15256
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00581
AC:
30
AN:
5164
South Asian (SAS)
AF:
0.000208
AC:
1
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10546
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67970
Other (OTH)
AF:
0.00
AC:
0
AN:
2104
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.00
Hom.:
0
Bravo
AF:
0.000325

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Benign:2
Dec 31, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 21, 2024
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

See Variant Classification Assertion Criteria. -

Mitochondrial DNA depletion syndrome, myopathic form Uncertain:1
Mar 18, 2016
Soonchunhyang University Bucheon Hospital, Soonchunhyang University Medical Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:reference population

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
2.3
Mutation Taster
=98/2
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs529176585; hg19: chr16-66547624; API