NM_001064.4:c.1540G>C

Variant names:

• chr3-53228089-C-G
• rs762983878
• NM_001064.4:c.1540G>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_001064.4(TKT):​c.1540G>C​(p.Glu514Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E514K) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TKT NM_001064.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.82
• Publications: 0 publications found

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]

TKT Gene-Disease associations (from GenCC):

• transketolase deficiency

  Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.861

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TKT	NM_001064.4	c.1540G>C	p.Glu514Gln	missense_variant	Exon 12 of 14	ENST00000462138.6	NP_001055.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TKT	ENST00000462138.6	c.1540G>C	p.Glu514Gln	missense_variant	Exon 12 of 14	1	NM_001064.4	ENSP00000417773.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.81	D;D;.;T
Eigen	Uncertain	0.67
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	.;D;D;D
M_CAP	Uncertain	0.27	D
MetaRNN	Pathogenic	0.86	D;D;D;D
MetaSVM	Uncertain	0.71	D
MutationAssessor	Uncertain	2.3	M;M;.;.
PhyloP100		7.8
PrimateAI	Uncertain	0.74	T
PROVEAN	Uncertain	-3.0	D;D;D;.
REVEL	Pathogenic	0.73
Sift	Benign	0.042	D;D;D;.
Sift4G	Uncertain	0.059	T;T;T;T
Polyphen		1.0	D;D;.;.
Vest4		0.80
MutPred		0.60		Loss of disorder (P = 0.3225);Loss of disorder (P = 0.3225);.;.;
MVP		0.88
MPC		1.1
ClinPred		0.99	D
GERP RS		5.4
Varity_R		0.77
gMVP		0.87
Mutation Taster		=16/84	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: rs762983878; hg19: chr3-53262105;