1-205058071-G-T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBS1_Supporting

The NM_005076.5(CNTN2):​c.215+6G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000136 in 1,612,916 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 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

CNTN2
NM_005076.5 splice_region, intron

Scores

2
Splicing: ADA: 0.00005850
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.262

Publications

0 publications found
Variant links:
Genes affected
CNTN2 (HGNC:2172): (contactin 2) This gene encodes a member of the contactin family of proteins, part of the immunoglobulin superfamily of cell adhesion molecules. The encoded glycosylphosphatidylinositol (GPI)-anchored neuronal membrane protein plays a role in the proliferation, migration, and axon guidance of neurons of the developing cerebellum. A mutation in this gene may be associated with adult myoclonic epilepsy. [provided by RefSeq, Sep 2016]
CNTN2 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • epilepsy, familial adult myoclonic, 5
    Inheritance: AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • benign adult familial myoclonic epilepsy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.69).
BS1
Variant frequency is greater than expected in population eas. GnomAdExome4 allele frequency = 0.0000137 (20/1460660) while in subpopulation EAS AF = 0.000378 (15/39678). AF 95% confidence interval is 0.000233. There are 0 homozygotes in GnomAdExome4. There are 7 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CNTN2NM_005076.5 linkc.215+6G>T splice_region_variant, intron_variant Intron 3 of 22 ENST00000331830.7 NP_005067.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CNTN2ENST00000331830.7 linkc.215+6G>T splice_region_variant, intron_variant Intron 3 of 22 1 NM_005076.5 ENSP00000330633.4

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152256
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000407
AC:
1
AN:
245448
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000649
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000137
AC:
20
AN:
1460660
Hom.:
0
Cov.:
32
AF XY:
0.00000963
AC XY:
7
AN XY:
726626
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44618
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26094
East Asian (EAS)
AF:
0.000378
AC:
15
AN:
39678
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86128
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52990
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111640
Other (OTH)
AF:
0.00
AC:
0
AN:
60270
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
2
3
5
6
8
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152256
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74392
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41476
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000192
AC:
1
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Epilepsy, familial adult myoclonic, 5 Uncertain:1
May 22, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 3 of the CNTN2 gene. It does not directly change the encoded amino acid sequence of the CNTN2 protein. It affects a nucleotide within the consensus splice site. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with CNTN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 2151270). Variants that disrupt 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 is not likely to affect RNA splicing. 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
-0.69
CADD
Benign
3.3
DANN
Benign
0.75
PhyloP100
-0.26

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000058
dbscSNV1_RF
Benign
0.0
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

Other links and lift over

dbSNP: rs370377460; hg19: chr1-205027199; API