rs1265314976

Variant names:

• chr7-144591499-A-G
• rs1265314976
• NM_022445.4:c.425T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_022445.4(TPK1):​c.425T>C​(p.Leu142Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,828 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L142F) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TPK1 NM_022445.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.84
• Publications: 2 publications found

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 Gene-Disease associations (from GenCC):

• childhood encephalopathy due to thiamine pyrophosphokinase deficiency

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia
• Leigh syndrome

  Inheritance: AR Classification: MODERATE Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-144591498-C-G is described in ClinVar as Pathogenic. ClinVar VariationId is 265278.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_022445.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TPK1	NM_022445.4	MANE Select	c.425T>C	p.Leu142Ser	missense	Exon 7 of 9	NP_071890.2
	TPK1	NM_001350879.1		c.425T>C	p.Leu142Ser	missense	Exon 7 of 9	NP_001337808.1	Q9H3S4-1
	TPK1	NM_001350881.1		c.425T>C	p.Leu142Ser	missense	Exon 7 of 10	NP_001337810.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TPK1	ENST00000360057.7	TSL:1 MANE Select	c.425T>C	p.Leu142Ser	missense	Exon 7 of 9	ENSP00000353165.3	Q9H3S4-1
	TPK1	ENST00000378098.8	TSL:1	n.*181T>C		non_coding_transcript_exon	Exon 8 of 10	ENSP00000367338.4	F8WCM7
	TPK1	ENST00000482940.5	TSL:1	n.*350T>C		non_coding_transcript_exon	Exon 9 of 12	ENSP00000449909.1	F8VVJ1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251362 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461828 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727226

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000447 AC: 2 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111952

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Childhood encephalopathy due to thiamine pyrophosphokinase deficiency (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Pathogenic	0.37	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	4.0	H
PhyloP100		7.8
PrimateAI	Uncertain	0.52	T
PROVEAN	Pathogenic	-5.4	D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.90		Loss of stability (P = 0.018)
MVP		0.89
MPC		0.78
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.94
gMVP		0.95
Mutation Taster		=7/93	disease causing

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

Other links and lift over

dbSNP: rs1265314976; hg19: chr7-144288592;