7-144453613-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PM5

The NM_022445.4(TPK1):​c.664G>A​(p.Asp222Asn) variant causes a missense change. The variant allele was found at a frequency of 0.0000242 in 1,613,800 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D222H) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

TPK1
NM_022445.4 missense

Scores

1
12
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.12
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1
In a chain Thiamin pyrophosphokinase 1 (size 242) in uniprot entity TPK1_HUMAN there are 17 pathogenic changes around while only 1 benign (94%) in NM_022445.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr7-144453613-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 419232.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
TPK1NM_022445.4 linkuse as main transcriptc.664G>A p.Asp222Asn missense_variant 9/9 ENST00000360057.7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
TPK1ENST00000360057.7 linkuse as main transcriptc.664G>A p.Asp222Asn missense_variant 9/91 NM_022445.4 P1Q9H3S4-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152066
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000725
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000358
AC:
9
AN:
251392
Hom.:
0
AF XY:
0.0000368
AC XY:
5
AN XY:
135866
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000528
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000239
AC:
35
AN:
1461616
Hom.:
0
Cov.:
30
AF XY:
0.0000234
AC XY:
17
AN XY:
727130
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000447
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152184
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74382
show subpopulations
Gnomad4 AFR
AF:
0.0000723
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000862
Hom.:
0
Bravo
AF:
0.0000529
ESP6500AA
AF:
0.000454
AC:
2
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

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
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 19, 2024This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 222 of the TPK1 protein (p.Asp222Asn). This variant is present in population databases (rs368458768, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with TPK1-related conditions. ClinVar contains an entry for this variant (Variation ID: 657167). 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 not expected to disrupt TPK1 protein function with a negative predictive value of 80%. 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
0.13
BayesDel_addAF
Benign
-0.16
T
BayesDel_noAF
Benign
-0.29
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.52
D;D;.
Eigen
Uncertain
0.37
Eigen_PC
Uncertain
0.32
FATHMM_MKL
Uncertain
0.85
D
M_CAP
Uncertain
0.21
D
MetaRNN
Uncertain
0.67
D;D;D
MetaSVM
Uncertain
-0.10
T
MutationAssessor
Pathogenic
3.1
M;.;.
MutationTaster
Benign
1.0
D;D;D;D
PrimateAI
Uncertain
0.58
T
PROVEAN
Uncertain
-3.7
D;D;D
REVEL
Uncertain
0.38
Sift
Uncertain
0.0070
D;D;D
Sift4G
Benign
0.13
T;T;T
Polyphen
1.0
D;D;D
Vest4
0.54
MVP
0.86
MPC
0.58
ClinPred
0.91
D
GERP RS
4.6
Varity_R
0.81
gMVP
0.69

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.

Other links and lift over

dbSNP: rs368458768; hg19: chr7-144150706; API