chr12-40908498-G-A

Position:

• chr12-40908498-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001843.4(CNTN1):​c.61+5G>A variant causes a splice donor 5th base, intron change. The variant allele was found at a frequency of 0.00000657 in 152,202 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: CNTN1 NM_001843.4 splice_donor_5th_base, intron
• Scores: Splicing: ADA: 0.8724
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.63

Genes affected

CNTN1 (HGNC:2171): (contactin 1) The protein encoded by this gene is a member of the immunoglobulin superfamily. It is a glycosylphosphatidylinositol (GPI)-anchored neuronal membrane protein that functions as a cell adhesion molecule. It may play a role in the formation of axon connections in the developing nervous system. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.36).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CNTN1	NM_001843.4	c.61+5G>A		splice_donor_5th_base_variant, intron_variant		ENST00000551295.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CNTN1	ENST00000551295.7	c.61+5G>A		splice_donor_5th_base_variant, intron_variant		1	NM_001843.4	P3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152202 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 25

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152202 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74356

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Compton-North congenital myopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 04, 2018

Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. This sequence change falls in intron 2 of the CNTN1 gene. It does not directly change the encoded amino acid sequence of the CNTN1 protein, but it affects a nucleotide within the consensus splice site of the intron. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with CNTN1-related disease. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.36
CADD	Uncertain	24
DANN	Benign	0.88

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.87
dbscSNV1_RF	Benign	0.60
SpliceAI score (max)		0.13		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: rs1944916936; hg19: chr12-41302300;