7-147132508-A-G

Variant names:

• chr7-147132508-A-G
• rs1554441906
• NM_014141.6:c.1347A>G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_014141.6(CNTNAP2):​c.1347A>G​(p.Ser449Ser) variant causes a splice region, synonymous change. The variant allele was found at a frequency of 0.00000411 in 1,461,224 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. S449S) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: CNTNAP2 NM_014141.6 splice_region, synonymous
• Scores: Splicing: ADA: 0.9678
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.01
• Publications: 0 publications found

Genes affected

CNTNAP2 (HGNC:13830): (contactin associated protein 2) This gene encodes a member of the neurexin family which functions in the vertebrate nervous system as cell adhesion molecules and receptors. This protein, like other neurexin proteins, contains epidermal growth factor repeats and laminin G domains. In addition, it includes an F5/8 type C domain, discoidin/neuropilin- and fibrinogen-like domains, thrombospondin N-terminal-like domains and a putative PDZ binding site. This protein is localized at the juxtaparanodes of myelinated axons, and mediates interactions between neurons and glia during nervous system development and is also involved in localization of potassium channels within differentiating axons. This gene encompasses almost 1.5% of chromosome 7 and is one of the largest genes in the human genome. It is directly bound and regulated by forkhead box protein P2, a transcription factor related to speech and language development. This gene has been implicated in multiple neurodevelopmental disorders, including Gilles de la Tourette syndrome, schizophrenia, epilepsy, autism, ADHD and intellectual disability. [provided by RefSeq, Jul 2017]

CNTNAP2 Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AR, AD Classification: DEFINITIVE, NO_KNOWN Submitted by: ClinGen
• cortical dysplasia-focal epilepsy syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Illumina, Labcorp Genetics (formerly Invitae), Orphanet, G2P, Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CNTNAP2	NM_014141.6	c.1347A>G	p.Ser449Ser	splice_region_variant, synonymous_variant	Exon 8 of 24	ENST00000361727.8	NP_054860.1
CNTNAP2	XM_017011950.3	c.1347A>G	p.Ser449Ser	splice_region_variant, synonymous_variant	Exon 8 of 14		XP_016867439.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CNTNAP2	ENST00000361727.8	c.1347A>G	p.Ser449Ser	splice_region_variant, synonymous_variant	Exon 8 of 24	1	NM_014141.6	ENSP00000354778.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1461224 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726912

African (AFR) AF: 0.00 AC: 0 AN: 33442

American (AMR) AF: 0.0000224 AC: 1 AN: 44638

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26108

East Asian (EAS) AF: 0.000126 AC: 5 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86232

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111586

Other (OTH) AF: 0.00 AC: 0 AN: 60356

GnomAD4 genome Cov.: 32

Asia WGS AF: 0.000289 AC: 1 AN: 3476

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cortical dysplasia-focal epilepsy syndrome Uncertain:1

Jun 13, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. This variant has not been reported in the literature in individuals affected with CNTNAP2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects codon 449 of the CNTNAP2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the CNTNAP2 protein. It affects a nucleotide within the consensus splice site. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.37
CADD	Benign	16
DANN	Benign	0.89
PhyloP100		4.0

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.97
dbscSNV1_RF	Pathogenic	0.82
SpliceAI score (max)		0.080		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: rs1554441906; hg19: chr7-146829600;