chr8-27469852-C-A

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001347705.2(CHRNA2):c.-225G>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,614,088 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 (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

CHRNA2
NM_001347705.2 5_prime_UTR_premature_start_codon_gain

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.113

Publications

6 publications found

Variant links:

Genes affected

CHRNA2 (HGNC:1956): (cholinergic receptor nicotinic alpha 2 subunit) Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels formed by a pentameric arrangement of alpha and beta subunits to create distinct muscle and neuronal receptors. Neuronal receptors are found throughout the peripheral and central nervous system where they are involved in fast synaptic transmission. This gene encodes an alpha subunit that is widely expressed in the brain. The proposed structure for nAChR subunits is a conserved N-terminal extracellular domain followed by three conserved transmembrane domains, a variable cytoplasmic loop, a fourth conserved transmembrane domain, and a short C-terminal extracellular region. Mutations in this gene cause autosomal dominant nocturnal frontal lobe epilepsy type 4. Single nucleotide polymorphisms (SNPs) in this gene have been associated with nicotine dependence. [provided by RefSeq, Nov 2009]

CHRNA2 Gene-Disease associations (from GenCC):

autosomal dominant nocturnal frontal lobe epilepsy 4
Inheritance: AD Classification: STRONG, LIMITED Submitted by: G2P, Illumina, Labcorp Genetics (formerly Invitae)
autosomal dominant nocturnal frontal lobe epilepsy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
familial sleep-related hypermotor epilepsy
Inheritance: AD Classification: LIMITED Submitted by: ClinGen
benign familial infantile epilepsy
Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
epilepsy
Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

CHRNA2 links:

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=0.10029814).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001347705.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
CHRNA2	NM_000742.4	MANE Select	c.203G>T	p.Arg68Leu	missense	Exon 3 of 7	NP_000733.2	Q15822-1
CHRNA2	NM_001347705.2		c.-225G>T		5_prime_UTR_premature_start_codon_gain	Exon 3 of 7	NP_001334634.1
CHRNA2	NM_001347706.2		c.-270G>T		5_prime_UTR_premature_start_codon_gain	Exon 3 of 7	NP_001334635.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
CHRNA2	ENST00000407991.3	TSL:5 MANE Select	c.203G>T	p.Arg68Leu	missense	Exon 3 of 7	ENSP00000385026.1	Q15822-1
CHRNA2	ENST00000523695.5	TSL:1	n.203G>T		non_coding_transcript_exon	Exon 3 of 7	ENSP00000430612.1	E5RJ54
CHRNA2	ENST00000240132.7	TSL:2	c.203G>T	p.Arg68Leu	missense	Exon 3 of 7	ENSP00000240132.2	Q15822-2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152128

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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:

0.000478

GnomAD2 exomes

AF:

0.00000398

AC:

AN:

251408

AF XY:

0.00

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

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:

0.00000205

AC:

AN:

1461842

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727220

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.0000224

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53368

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1112012

Other (OTH)

AF:

0.0000331

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.458

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000263

AC:

AN:

152246

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74432

show subpopulations

African (AFR)

AF:

0.0000241

AC:

AN:

41556

American (AMR)

AF:

0.000131

AC:

AN:

15304

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5164

South Asian (SAS)

AF:

0.00

AC:

AN:

4808

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10610

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68014

Other (OTH)

AF:

0.000473

AC:

AN:

2112

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.463

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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.:

Bravo

AF:

0.0000302

ExAC

AF:

0.00000824

AC:

ClinVar

ClinVar submissions

Significance:Uncertain significance

Revision:criteria provided, single submitter

View on ClinVar

Pathogenic

VUS

Benign

Condition

Autosomal dominant nocturnal frontal lobe epilepsy (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.097

BayesDel_addAF

Benign

-0.15

BayesDel_noAF

Benign

-0.37

CADD

Benign

(source)

DANN

Uncertain

0.99

DEOGEN2

Benign

0.33

Eigen

Benign

-0.37

Eigen_PC

Benign

-0.32

FATHMM_MKL

Benign

0.12

LIST_S2

Benign

0.85

M_CAP

Benign

0.041

MetaRNN

Benign

0.10

MetaSVM

Benign

-0.84

MutationAssessor

Benign

1.6

PhyloP100

0.11

PrimateAI

Benign

0.32

PROVEAN

Benign

-1.6

REVEL

Benign

0.12

Sift

Uncertain

0.026

Sift4G

Uncertain

0.048

Polyphen

0.051

Vest4

0.24

MutPred

0.52

Loss of MoRF binding (P = 0.0011)

MVP

0.63

MPC

0.27

ClinPred

0.32

GERP RS

3.9

Varity_R

0.52

gMVP

0.42

Mutation Taster

=75/25

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over