chr18-55223016-A-G

Position:

• chr18-55223016-A-G

Variant summary

Our verdict is Benign. Variant got -12 ACMG points: 0P and 12B. BP4_Moderate BP6_Moderate BS1 BS2

The NM_001083962.2(TCF4):​c.*5019T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00228 in 152,330 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★).

• Frequency:
  • Genomes: 𝑓 0.0023 (2 hom., cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TCF4 NM_001083962.2 3_prime_UTR
• Clinical Significance: Benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.538

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]

ACMG classification

Verdict is Benign. Variant got -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP6: Variant 18-55223016-A-G is Benign according to our data. Variant chr18-55223016-A-G is described in ClinVar as [Benign]. Clinvar id is 327232.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00228 (348/152330) while in subpopulation AFR AF= 0.0069 (287/41566). AF 95% confidence interval is 0.00625. There are 2 homozygotes in gnomad4. There are 171 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 348 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TCF4	NM_001083962.2	c.*5019T>C		3_prime_UTR_variant	20/20	ENST00000354452.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TCF4	ENST00000354452.8	c.*5019T>C		3_prime_UTR_variant	20/20	5	NM_001083962.2	P3

Frequencies

GnomAD3 genomes AF: 0.00226 AC: 344 AN: 152212 Hom.: 2 Cov.: 33

Gnomad AFR AF: 0.00680

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000785

Gnomad ASJ AF: 0.00835

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000206

Gnomad OTH AF: 0.00239

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 190 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 116

Gnomad4 FIN exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00228 AC: 348 AN: 152330 Hom.: 2 Cov.: 33 AF XY: 0.00230 AC XY: 171 AN XY: 74492

Gnomad4 AFR AF: 0.00690

Gnomad4 AMR AF: 0.000784

Gnomad4 ASJ AF: 0.00835

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000206

Gnomad4 OTH AF: 0.00237

Alfa AF: 0.00156 Hom.: 0

Bravo AF: 0.00245

Asia WGS AF: 0.00173 AC: 6 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pitt-Hopkins syndrome Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
CADD	Benign	2.9
DANN	Benign	0.80

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs140368699; hg19: chr18-52890247;