chr18-55461088-G-C

Position:

• chr18-55461088-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_001083962.2(TCF4):​c.235C>G​(p.His79Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: TCF4 NM_001083962.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.61

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-AS1 (HGNC:51642): (TCF4 antisense RNA 1)

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TCF4. . Gene score misZ: 4.1035 (greater than the threshold 3.09). Trascript score misZ: 4.5676 (greater than threshold 3.09). The gene has 42 curated pathogenic missense variants (we use a threshold of 10). The gene has 70 curated benign missense variants. GenCC has associacion of the gene with intellectual disability, corneal dystrophy, Fuchs endothelial, 3, autosomal dominant non-syndromic intellectual disability, autism spectrum disorder, Fuchs' endothelial dystrophy, Pitt-Hopkins syndrome.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TCF4	NM_001083962.2	c.235C>G	p.His79Asp	missense_variant	5/20	ENST00000354452.8	NP_001077431.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TCF4	ENST00000354452.8	c.235C>G	p.His79Asp	missense_variant	5/20	5	NM_001083962.2	ENSP00000346440.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Pitt-Hopkins syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 06, 2022

This sequence change replaces histidine, which is basic and polar, with aspartic acid, which is acidic and polar, at codon 79 of the TCF4 protein (p.His79Asp). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TCF4-related conditions. ClinVar contains an entry for this variant (Variation ID: 1331336). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 30, 2021

Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 22045651, 27535533) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.090
CADD	Pathogenic	28
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.54	.;D;.;T;.;D;.;.;.;.;.;.;T;.;.;.;.;.;.;.;T;.;.;T;.;.;T;T;T;.;.
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.55
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.97	D;.;.;D;D;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	0.018	T
MetaRNN	Uncertain	0.47	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	-0.84	T
MutationAssessor	Benign	0.24	.;N;.;.;.;N;N;N;.;.;.;.;.;N;.;N;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PrimateAI	Uncertain	0.72	T
PROVEAN	Benign	-2.1	.;N;.;.;.;N;N;.;N;N;N;N;N;N;.;N;.;N;N;.;D;.;.;.;.;D;.;D;D;.;D
REVEL	Benign	0.24
Sift	Benign	0.24	.;T;.;.;.;T;T;.;T;T;T;T;T;T;.;T;.;T;T;.;T;.;.;.;.;T;.;T;T;.;T
Sift4G	Benign	0.20	T;T;.;.;.;T;T;T;T;T;T;T;T;T;T;T;T;T;T;.;.;.;T;T;T;.;.;T;T;T;.
Polyphen		0.015, 0.99	.;B;.;.;.;B;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.88
MutPred		0.21		.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;Loss of catalytic residue at H181 (P = 0.0076);.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.70
MPC		0.86
ClinPred		0.71	D
GERP RS		6.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.15
gMVP		0.47

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: rs957698131; hg19: chr18-53128319;