NM_005076.5:c.2677C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4BS1_Supporting

The NM_005076.5(CNTN2):​c.2677C>T​(p.Arg893Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000121 in 1,613,808 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R893Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

CNTN2
NM_005076.5 missense

Scores

2
10
7

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.907

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 -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.3453165).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000125 (19/152172) while in subpopulation NFE AF = 0.000162 (11/68038). AF 95% confidence interval is 0.0000905. There are 0 homozygotes in GnomAd4. There are 6 alleles in the male GnomAd4 subpopulation. Median coverage is 33. 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.2677C>T p.Arg893Trp missense_variant Exon 20 of 23 ENST00000331830.7 NP_005067.1 Q02246A1ML24A1L3A3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CNTN2ENST00000331830.7 linkc.2677C>T p.Arg893Trp missense_variant Exon 20 of 23 1 NM_005076.5 ENSP00000330633.4 Q02246

Frequencies

GnomAD3 genomes
AF:
0.000125
AC:
19
AN:
152172
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000965
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000188
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000162
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000120
AC:
30
AN:
250932
AF XY:
0.0000959
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.000299
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000925
Gnomad NFE exome
AF:
0.000168
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000120
AC:
176
AN:
1461636
Hom.:
0
Cov.:
34
AF XY:
0.000107
AC XY:
78
AN XY:
727148
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33474
American (AMR)
AF:
0.0000895
AC:
4
AN:
44694
Ashkenazi Jewish (ASJ)
AF:
0.000230
AC:
6
AN:
26120
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.0000696
AC:
6
AN:
86230
European-Finnish (FIN)
AF:
0.000356
AC:
19
AN:
53344
Middle Eastern (MID)
AF:
0.000175
AC:
1
AN:
5722
European-Non Finnish (NFE)
AF:
0.000118
AC:
131
AN:
1111974
Other (OTH)
AF:
0.000116
AC:
7
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
10
21
31
42
52
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.000125
AC:
19
AN:
152172
Hom.:
0
Cov.:
33
AF XY:
0.0000807
AC XY:
6
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.0000965
AC:
4
AN:
41442
American (AMR)
AF:
0.0000655
AC:
1
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.000188
AC:
2
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000162
AC:
11
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.533
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

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:
0.000230
Hom.:
0
Bravo
AF:
0.0000907
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.000115
AC:
14
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
May 21, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2677C>T (p.R893W) alteration is located in exon 20 (coding exon 19) of the CNTN2 gene. This alteration results from a C to T substitution at nucleotide position 2677, causing the arginine (R) at amino acid position 893 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Epilepsy, familial adult myoclonic, 5 Uncertain:1
Sep 19, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 893 of the CNTN2 protein (p.Arg893Trp). This variant is present in population databases (rs149814483, gnomAD 0.03%). 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: 541412). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CNTN2 protein function. 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
AlphaMissense
Uncertain
0.54
BayesDel_addAF
Benign
-0.18
T
BayesDel_noAF
Benign
-0.23
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.25
T;T;.
Eigen
Uncertain
0.35
Eigen_PC
Uncertain
0.24
FATHMM_MKL
Uncertain
0.82
D
LIST_S2
Uncertain
0.97
.;.;D
M_CAP
Benign
0.056
D
MetaRNN
Benign
0.35
T;T;T
MetaSVM
Uncertain
-0.027
T
MutationAssessor
Pathogenic
3.1
M;M;.
PhyloP100
0.91
PrimateAI
Uncertain
0.73
T
PROVEAN
Benign
-1.9
.;N;.
REVEL
Uncertain
0.34
Sift
Uncertain
0.0060
.;D;.
Sift4G
Uncertain
0.0070
.;D;.
Polyphen
1.0
D;D;.
Vest4
0.64
MVP
0.87
MPC
1.3
ClinPred
0.55
D
GERP RS
-0.70
Varity_R
0.11
gMVP
0.71
Mutation Taster
=76/24
polymorphism

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

Other links and lift over

dbSNP: rs149814483; hg19: chr1-205041207; COSMIC: COSV59347739; COSMIC: COSV59347739; API