chr20-23390261-T-C

Variant summary

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

The NM_022080.3(NAPB):​c.424A>G​(p.Ile142Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000116 in 1,609,614 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. I142T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

NAPB
NM_022080.3 missense

Scores

1
3
15

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.02

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

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=0.18342903).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NAPBNM_022080.3 linkc.424A>G p.Ile142Val missense_variant Exon 6 of 11 ENST00000377026.4 NP_071363.1 Q9H115-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NAPBENST00000377026.4 linkc.424A>G p.Ile142Val missense_variant Exon 6 of 11 1 NM_022080.3 ENSP00000366225.4 Q9H115-1

Frequencies

GnomAD3 genomes
AF:
0.0000657
AC:
10
AN:
152256
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000941
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000678
AC:
17
AN:
250792
AF XY:
0.0000885
show subpopulations
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:
0.0000462
Gnomad NFE exome
AF:
0.000132
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000121
AC:
177
AN:
1457358
Hom.:
0
Cov.:
29
AF XY:
0.000134
AC XY:
97
AN XY:
725314
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33406
American (AMR)
AF:
0.00
AC:
0
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39658
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86074
European-Finnish (FIN)
AF:
0.0000936
AC:
5
AN:
53400
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
0.000151
AC:
167
AN:
1108032
Other (OTH)
AF:
0.0000664
AC:
4
AN:
60240
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.446
Heterozygous variant carriers
0
8
16
24
32
40
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000657
AC:
10
AN:
152256
Hom.:
0
Cov.:
33
AF XY:
0.0000538
AC XY:
4
AN XY:
74392
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41470
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.0000941
AC:
1
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.000107
Hom.:
0
Bravo
AF:
0.0000453
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.000164
EpiControl
AF:
0.000119

ClinVar

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

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Oct 03, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.424A>G (p.I142V) alteration is located in exon 6 (coding exon 6) of the NAPB gene. This alteration results from a A to G substitution at nucleotide position 424, causing the isoleucine (I) at amino acid position 142 to be replaced by a valine (V). 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
0.057
BayesDel_addAF
Benign
-0.16
T
BayesDel_noAF
Benign
-0.23
CADD
Benign
21
DANN
Uncertain
0.99
DEOGEN2
Benign
0.090
.;.;.;T
Eigen
Benign
-0.081
Eigen_PC
Benign
0.11
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.91
D;D;D;D
M_CAP
Benign
0.011
T
MetaRNN
Benign
0.18
T;T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
1.5
.;.;.;L
PhyloP100
8.0
PrimateAI
Uncertain
0.75
T
PROVEAN
Benign
-0.41
N;N;.;N
REVEL
Benign
0.19
Sift
Benign
0.30
T;T;.;T
Sift4G
Benign
0.44
T;T;T;T
Polyphen
0.0090
.;.;.;B
Vest4
0.47
MVP
0.24
MPC
0.55
ClinPred
0.18
T
GERP RS
5.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.098
gMVP
0.23
Mutation Taster
=47/53
disease causing

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: rs200550616; hg19: chr20-23370898; API