rs1555718506

Positions:

• chr19-10361525-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_003331.5(TYK2):​c.2033T>C​(p.Val678Ala) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: TYK2 NM_003331.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.94

Genes affected

TYK2 (HGNC:12440): (tyrosine kinase 2) This gene encodes a member of the tyrosine kinase and, more specifically, the Janus kinases (JAKs) protein families. This protein associates with the cytoplasmic domain of type I and type II cytokine receptors and promulgate cytokine signals by phosphorylating receptor subunits. It is also a component of both the type I and type III interferon signaling pathways. As such, it may play a role in anti-viral immunity. A mutation in this gene has been associated with Immunodeficiency 35. [provided by RefSeq, Sep 2020]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.839

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TYK2	NM_003331.5	c.2033T>C	p.Val678Ala	missense_variant	14/25	ENST00000525621.6	NP_003322.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TYK2	ENST00000525621.6	c.2033T>C	p.Val678Ala	missense_variant	14/25	1	NM_003331.5	ENSP00000431885.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 24, 2024

The c.2033T>C (p.V678A) alteration is located in exon 14 (coding exon 12) of the TYK2 gene. This alteration results from a T to C substitution at nucleotide position 2033, causing the valine (V) at amino acid position 678 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Immunodeficiency 35 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 05, 2017

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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with TYK2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces valine with alanine at codon 678 of the TYK2 protein (p.Val678Ala). The valine residue is highly conserved and there is a small physicochemical difference between valine and alanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.44	T;T;T;.
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.33
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Uncertain	0.91	D;D;.;D
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.84	D;D;D;D
MetaSVM	Uncertain	0.20	D
MutationAssessor	Benign	1.6	L;.;L;.
PrimateAI	Uncertain	0.63	T
PROVEAN	Uncertain	-3.6	D;D;D;D
REVEL	Uncertain	0.55
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Uncertain	0.0040	D;D;D;D
Polyphen		1.0	D;.;D;D
Vest4		0.74
MutPred		0.42		Gain of sheet (P = 0.1539);.;Gain of sheet (P = 0.1539);Gain of sheet (P = 0.1539);
MVP		0.82
MPC		1.0
ClinPred		0.99	D
GERP RS		3.7
Varity_R		0.56
gMVP		0.51

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

Other links and lift over

dbSNP: rs1555718506; hg19: chr19-10472201;