Genetic Variant TPK1:p.Pro234Ser (chr7-144453577-G-A) – ACMG Classification: Uncertain_significance (4 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PM2

The NM_022445.4(TPK1):c.700C>T(p.Pro234Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,610 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TPK1
NM_022445.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.58

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:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 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;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TPK1	NM_022445.4 link	c.700C>T	p.Pro234Ser	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.700C>T	p.Pro234Ser	missense_variant	Exon 9 of 9	1	NM_022445.4	ENSP00000353165.3		Q9H3S4-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251418

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135874

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

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:

6.84e-7

AC:

AN:

1461610

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727134

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.000111

Hom.:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Childhood encephalopathy due to thiamine pyrophosphokinase deficiency

Uncertain:1

Dec 19, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline with serine at codon 234 of the TPK1 protein (p.Pro234Ser). The proline residue is moderately conserved and there is a moderate physicochemical difference between proline and serine. This variant is present in population databases (rs748307256, ExAC 0.001%). This variant has not been reported in the literature in individuals with TPK1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.20

BayesDel_addAF

Pathogenic

0.21

BayesDel_noAF

Uncertain

0.070

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.71

D;D;.

Eigen

Uncertain

0.58

Eigen_PC

Uncertain

0.54

FATHMM_MKL

Uncertain

0.94

M_CAP

Benign

0.079

MetaRNN

Uncertain

0.68

D;D;D

MetaSVM

Uncertain

-0.089

MutationAssessor

Uncertain

2.5

M;.;.

PrimateAI

Benign

0.45

PROVEAN

Pathogenic

-5.2

D;D;D

REVEL

Uncertain

0.58

Sift

Benign

0.17

T;T;T

Sift4G

Benign

0.31

T;T;T

Polyphen

1.0

D;D;D

Vest4

0.56

MutPred

0.69

Gain of disorder (P = 0.0779);.;.;

MVP

0.79

MPC

0.65

ClinPred

0.99

GERP RS

5.8

Varity_R

0.58

gMVP

0.83

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