20-23395175-G-C

Variant names:

Variant summary

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

The NM_022080.3(NAPB):c.306C>G(p.Asn102Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000013 in 1,614,034 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict 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. N102D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

NAPB
NM_022080.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.25

Publications

0 publications found

Variant links:

Genes affected

NAPB (HGNC:15751): (NSF attachment protein beta) This gene encodes a member of the soluble N-ethyl-maleimide-sensitive fusion attachment protein (SNAP) family. SNAP proteins play a critical role in the docking and fusion of vesicles to target membranes as part of the 20S NSF-SNAP-SNARE complex. This gene encodes the SNAP beta isoform which has been shown to be preferentially expressed in brain tissue. The encoded protein also interacts with the GluR2 α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor subunit C-terminus and may play a role as a chaperone in the molecular processing of the AMPA receptor. [provided by RefSeq, Mar 2017]

NAPB Gene-Disease associations (from GenCC):

developmental and epileptic encephalopathy 107
Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P

NAPB 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=0.1998102).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NAPB	NM_022080.3 link	c.306C>G	p.Asn102Lys	missense_variant	Exon 4 of 11	ENST00000377026.4	NP_071363.1	Q9H115-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NAPB	ENST00000377026.4 link	c.306C>G	p.Asn102Lys	missense_variant	Exon 4 of 11	1	NM_022080.3	ENSP00000366225.4		Q9H115-1

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152194

Hom.:

Cov.:

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:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000239

AC:

AN:

251000

AF XY:

0.0000295

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:

0.0000265

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000109

AC:

AN:

1461840

Hom.:

Cov.:

AF XY:

0.0000110

AC XY:

AN XY:

727220

show subpopulations

African (AFR)

AF:

0.0000597

AC:

AN:

33478

American (AMR)

AF:

0.0000224

AC:

AN:

44722

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26132

East Asian (EAS)

AF:

0.00

AC:

AN:

39692

South Asian (SAS)

AF:

0.0000116

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.000520

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00000809

AC:

AN:

1111978

Other (OTH)

AF:

0.00

AC:

AN:

60392

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.413

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152194

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74344

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41432

American (AMR)

AF:

0.00

AC:

AN:

15290

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5200

South Asian (SAS)

AF:

0.00

AC:

AN:

4832

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10610

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000735

AC:

AN:

68038

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.505

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.0000564

Hom.:

Bravo

AF:

0.0000604

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Mar 30, 2025

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The c.306C>G (p.N102K) alteration is located in exon 4 (coding exon 4) of the NAPB gene. This alteration results from a C to G substitution at nucleotide position 306, causing the asparagine (N) at amino acid position 102 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.20

BayesDel_addAF

Benign

-0.18

BayesDel_noAF

Benign

-0.40

CADD

Uncertain

(source)

DANN

Uncertain

0.98

DEOGEN2

Benign

0.17

.;.;T

Eigen

Benign

-0.085

Eigen_PC

Benign

0.15

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.89

D;D;D

M_CAP

Benign

0.032

MetaRNN

Benign

0.20

T;T;T

MetaSVM

Benign

-0.78

MutationAssessor

Benign

0.69

.;.;N

PhyloP100

6.3

PrimateAI

Pathogenic

0.81

PROVEAN

Benign

-1.8

N;.;N

REVEL

Benign

0.19

Sift

Benign

0.14

T;.;T

Sift4G

Benign

0.28

T;T;T

Polyphen

0.0020

.;.;B

Vest4

0.33

MutPred

0.38

.;.;Gain of methylation at N102 (P = 0.0037);

MVP

0.43

MPC

0.65

ClinPred

0.32

GERP RS

5.6

Varity_R

0.46

gMVP

0.46

Mutation Taster

=48/52

disease causing

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.070

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.

20-23395175-G-C

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over