rs1555722023

Variant names:

• chr18-55234565-G-C
• rs1555722023
• NM_001083962.2:c.1469C>G

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 6P and 1B. PM1 PM2 PP5_Moderate BP4

The NM_001083962.2(TCF4):​c.1469C>G​(p.Pro490Arg) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P490S) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TCF4 NM_001083962.2 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 4.45
• Publications: 0 publications found

Genes affected

TCF4 (HGNC:11634): (transcription factor 4) This gene encodes transcription factor 4, a basic helix-loop-helix transcription factor. The encoded protein recognizes an Ephrussi-box ('E-box') binding site ('CANNTG') - a motif first identified in immunoglobulin enhancers. This gene is broadly expressed, and may play an important role in nervous system development. Defects in this gene are a cause of Pitt-Hopkins syndrome. In addition, an intronic CTG repeat normally numbering 10-37 repeat units can expand to >50 repeat units and cause Fuchs endothelial corneal dystrophy. Multiple alternatively spliced transcript variants that encode different proteins have been described. [provided by RefSeq, Jul 2016]

TCF4 Gene-Disease associations (from GenCC):

• Pitt-Hopkins syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet, G2P, ClinGen
• corneal dystrophy, Fuchs endothelial, 3

  Inheritance: AD Classification: STRONG Submitted by: G2P
• autosomal dominant non-syndromic intellectual disability

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Fuchs' endothelial dystrophy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autism spectrum disorder

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• intellectual disability

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 9 uncertain in NM_001083962.2
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 18-55234565-G-C is Pathogenic according to our data. Variant chr18-55234565-G-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 468947.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP4: Computational evidence support a benign effect (MetaRNN=0.25764036). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TCF4	NM_001083962.2	c.1469C>G	p.Pro490Arg	missense_variant	Exon 16 of 20	ENST00000354452.8	NP_001077431.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TCF4	ENST00000354452.8	c.1469C>G	p.Pro490Arg	missense_variant	Exon 16 of 20	5	NM_001083962.2	ENSP00000346440.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pitt-Hopkins syndrome Pathogenic:1

Mar 05, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline with arginine at codon 490 of the TCF4 protein (p.Pro490Arg). The proline residue is moderately conserved and there is a moderate physicochemical difference between proline and arginine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a TCF4-related disease. Family studies indicate this variant likely was not inherited from either parent (i.e. occurred de novo) in an individual with disease (Invitae database). 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: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). In summary, this variant is a novel de novo missense change observed in an affected individual which suggests it is pathogenic, however, in the absence of functional data, it has been classified as Likely Pathogenic.. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Uncertain	0.014	T
BayesDel_noAF	Benign	-0.22
CADD	Uncertain	25
DANN	Uncertain	0.98
DEOGEN2	Benign	0.035	.;T;D;.;T;T;T;.;.;D;.;.;.;.;.;.;.;T;.;.;.;.;.;.;.;.;.;.;.;.;.
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Uncertain	0.94	D;.;.;.;D;D;D;D;D;D;.;D;.;D;D;D;D;D;.;D;.;D;D;D;D;D;.;D;D;D;D
M_CAP	Benign	0.011	T
MetaRNN	Benign	0.26	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-1.2	T
MutationAssessor	Benign	1.9	.;.;L;.;.;.;.;.;.;L;L;L;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		4.4
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-1.0	.;.;N;.;.;.;.;.;N;N;N;.;N;N;N;N;N;N;N;N;N;N;N;N;.;N;.;N;N;N;.
REVEL	Benign	0.12
Sift	Benign	0.034	.;.;D;.;.;.;.;.;D;D;T;.;D;D;D;D;D;D;D;T;D;D;T;D;.;D;.;T;D;D;.
Sift4G	Benign	0.084	T;.;T;.;.;.;.;.;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
Polyphen		0.61, 0.93	.;.;P;.;.;.;.;.;.;P;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;P;.;.
Vest4		0.31
MutPred		0.15		.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;Loss of catalytic residue at P591 (P = 0.0393);.;.;
MVP		0.43
MPC		2.0
ClinPred		0.84	D
GERP RS		5.5
Varity_R		0.11
gMVP		0.52
Mutation Taster		=62/38	disease causing (ClinVar)

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: rs1555722023; hg19: chr18-52901796;