1-205066593-C-G

Variant names:

• chr1-205066593-C-G
• rs2305276
• NM_005076.5:c.1969C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_005076.5(CNTN2):​c.1969C>G​(p.Arg657Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,754 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R657Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CNTN2 NM_005076.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.16
• Publications: 7 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005076.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CNTN2	NM_005076.5	MANE Select	c.1969C>G	p.Arg657Gly	missense	Exon 15 of 23	NP_005067.1	Q02246
	CNTN2	NM_001346083.2		c.1969C>G	p.Arg657Gly	missense	Exon 15 of 23	NP_001333012.1	Q02246
	CNTN2	NR_144350.2		n.2238C>G		non_coding_transcript_exon	Exon 15 of 23

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CNTN2	ENST00000331830.7	TSL:1 MANE Select	c.1969C>G	p.Arg657Gly	missense	Exon 15 of 23	ENSP00000330633.4	Q02246
	CNTN2	ENST00000640428.1	TSL:5	c.1969C>G	p.Arg657Gly	missense	Exon 15 of 23	ENSP00000491474.1	A0A1W2PQ11
	CNTN2	ENST00000853779.1		c.2020C>G	p.Arg674Gly	missense	Exon 16 of 24	ENSP00000523838.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152238 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250808 AF XY: 0.00

Gnomad AFR exome AF: 0.00

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: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461516 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727072

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44708

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26114

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86218

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53222

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111920

Other (OTH) AF: 0.0000166 AC: 1 AN: 60388

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152238 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74364

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41466

American (AMR) AF: 0.00 AC: 0 AN: 15274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5204

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68048

Other (OTH) AF: 0.00 AC: 0 AN: 2088

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.32
BayesDel_addAF	Uncertain	0.072	D
BayesDel_noAF	Benign	-0.14
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Benign	0.26	T
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.55
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.89	D
M_CAP	Benign	0.036	D
MetaRNN	Uncertain	0.46	T
MetaSVM	Benign	-0.94	T
MutationAssessor	Benign	1.2	L
PhyloP100		3.2
PrimateAI	Uncertain	0.62	T
PROVEAN	Uncertain	-2.8	D
REVEL	Uncertain	0.29
Sift	Uncertain	0.014	D
Sift4G	Benign	0.095	T
Polyphen		0.99	D
Vest4		0.71
MutPred		0.56		Loss of MoRF binding (P = 0.0304)
MVP		0.83
MPC		1.4
ClinPred		0.93	D
GERP RS		6.1
Varity_R		0.36
gMVP		0.65
Mutation Taster		=38/62	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs2305276; hg19: chr1-205035721;