3-53228343-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_001064.4(TKT):c.1412G>A(p.Arg471Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,950 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 (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: TKT NM_001064.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.82

Genes affected

TKT (HGNC:11834): (transketolase) This gene encodes a thiamine-dependent enzyme which plays a role in the channeling of excess sugar phosphates to glycolysis in the pentose phosphate pathway. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Apr 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.979

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TKT	NM_001064.4	c.1412G>A	p.Arg471Gln	missense_variant	11/14	ENST00000462138.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TKT	ENST00000462138.6	c.1412G>A	p.Arg471Gln	missense_variant	11/14	1	NM_001064.4	P3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152160 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461790 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727204

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152160 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74342

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

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

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 10, 2022

The c.1412G>A (p.R471Q) alteration is located in exon 11 (coding exon 11) of the TKT gene. This alteration results from a G to A substitution at nucleotide position 1412, causing the arginine (R) at amino acid position 471 to be replaced by a glutamine (Q). 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	0.95
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
Cadd	Pathogenic	34
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.92	D;D;.;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.65	D
MetaRNN	Pathogenic	0.98	D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.8	H;H;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Uncertain	-4.0	D;D;D;.
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D;D;.
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;D;.;.
Vest4		0.93
MutPred		0.85		Loss of catalytic residue at R471 (P = 0.1298);Loss of catalytic residue at R471 (P = 0.1298);.;.;
MVP		0.96
MPC		0.64
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.99
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.14		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

Other links and lift over

dbSNP: rs1204236713; hg19: chr3-53262359; COSMIC: COSV105894052; COSMIC: COSV105894052;