7-144453621-T-C

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_022445.4(TPK1):c.656A>G(p.Asn219Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000991 in 1,613,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

TPK1
NM_022445.4 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:4U:1

Conservation

PhyloP100: 5.26

Variant links:

Genes affected

TPK1 (HGNC:17358): (thiamin pyrophosphokinase 1) The protein encoded by this gene functions as a homodimer and catalyzes the conversion of thiamine to thiamine pyrophosphate, a cofactor for some enzymes of the glycolytic and energy production pathways. Defects in this gene are a cause of thiamine metabolism dysfunction syndrome-5. [provided by RefSeq, Apr 2017]

TPK1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1

In a chain Thiamin pyrophosphokinase 1 (size 242) in uniprot entity TPK1_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_022445.4

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.972

PP5

Variant 7-144453621-T-C is Pathogenic according to our data. Variant chr7-144453621-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 30572.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TPK1	NM_022445.4 link	c.656A>G	p.Asn219Ser	missense_variant	Exon 9 of 9	ENST00000360057.7	NP_071890.2	Q9H3S4-1A0A090N8Y0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TPK1	ENST00000360057.7 link	c.656A>G	p.Asn219Ser	missense_variant	Exon 9 of 9	1	NM_022445.4	ENSP00000353165.3		Q9H3S4-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152192

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251414

Hom.:

AF XY:

0.0000294

AC XY:

AN XY:

135876

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000579

Gnomad ASJ exome

AF:

0.000198

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461624

Hom.:

Cov.:

AF XY:

0.0000110

AC XY:

AN XY:

727132

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.000115

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000720

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152192

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000288

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000585

Hom.:

Bravo

AF:

0.0000227

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Childhood encephalopathy due to thiamine pyrophosphokinase deficiency

Pathogenic:3

Apr 02, 2020

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PS4,PM2,PM3,PP2,PP3. -

Dec 09, 2011

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Feb 01, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 219 of the TPK1 protein (p.Asn219Ser). This variant is present in population databases (rs371271054, gnomAD 0.02%). This missense change has been observed in individual(s) with thiamine metabolism dysfunction syndrome (PMID: 22152682, 28747443). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 30572). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt TPK1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects TPK1 function (PMID: 30483896). For these reasons, this variant has been classified as Pathogenic. -

not provided

Pathogenic:1

Jun 17, 2015

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The N219S missense variant in the TPK1 gene has been reported previously in association with thiaminepyrophosphokinase deficiency in a patient who was compound heterozygous for N219S and a frameshiftvariant (Mayr et al. 2011). N219S occurs at a position that is conserved across species, in silico analysispredicts that N219S is probably damaging to the protein structure/function, and a missense variant in anearby residue (D222H) has also been reported in the Human Gene Mutation Database in association withthiamine pyrophosphokinase deficiency (Stenson et al., 2014), supporting the functional importance of thisregion of the protein. Therefore, we interpret N219S to be a pathogenic variant. -

Inborn genetic diseases

Uncertain:1

May 25, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: flagged submission

Collection Method: clinical testing

The c.656A>G (p.N219S) alteration is located in exon 9 (coding exon 8) of the TPK1 gene. This alteration results from a A to G substitution at nucleotide position 656, causing the asparagine (N) at amino acid position 219 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.69

BayesDel_addAF

Uncertain

0.16

BayesDel_noAF

Pathogenic

0.16

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.92

D;D;.

Eigen

Pathogenic

0.93

Eigen_PC

Pathogenic

0.84

FATHMM_MKL

Uncertain

0.91

M_CAP

Pathogenic

0.81

MetaRNN

Pathogenic

0.97

D;D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

3.7

H;.;.

PrimateAI

Uncertain

0.59

PROVEAN

Pathogenic

-4.6

D;D;D

REVEL

Pathogenic

0.89

Sift

Pathogenic

0.0

D;D;D

Sift4G

Uncertain

0.0050

D;D;D

Polyphen

1.0

D;D;D

Vest4

0.91

MVP

0.88

MPC

0.59

ClinPred

0.99

GERP RS

5.8

Varity_R

0.96

gMVP

0.91

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