18-23586337-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP2

The NM_000271.5(NPC1):​c.7G>A​(p.Ala3Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000179 in 1,533,936 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. A3P) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00019 ( 0 hom. )

Consequence

NPC1
NM_000271.5 missense

Scores

7
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 0.597

Publications

2 publications found
Variant links:
Genes affected
NPC1 (HGNC:7897): (NPC intracellular cholesterol transporter 1) This gene encodes a large protein that resides in the limiting membrane of endosomes and lysosomes and mediates intracellular cholesterol trafficking via binding of cholesterol to its N-terminal domain. It is predicted to have a cytoplasmic C-terminus, 13 transmembrane domains, and 3 large loops in the lumen of the endosome - the last loop being at the N-terminus. This protein transports low-density lipoproteins to late endosomal/lysosomal compartments where they are hydrolized and released as free cholesterol. Defects in this gene cause Niemann-Pick type C disease, a rare autosomal recessive neurodegenerative disorder characterized by over accumulation of cholesterol and glycosphingolipids in late endosomal/lysosomal compartments.[provided by RefSeq, Aug 2009]
NPC1 Gene-Disease associations (from GenCC):
  • Niemann-Pick disease, type C1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Laboratory for Molecular Medicine, G2P
  • Niemann-Pick disease type C, adult neurologic onset
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Niemann-Pick disease type C, juvenile neurologic onset
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Niemann-Pick disease type C, late infantile neurologic onset
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Niemann-Pick disease type C, severe early infantile neurologic onset
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Niemann-Pick disease type C, severe perinatal form
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 171 curated pathogenic missense variants (we use a threshold of 10). The gene has 18 curated benign missense variants. Gene score misZ: 1.0917 (below the threshold of 3.09). Trascript score misZ: 1.706 (below the threshold of 3.09). GenCC associations: The gene is linked to Niemann-Pick disease, type C1, Niemann-Pick disease type C, severe early infantile neurologic onset, Niemann-Pick disease type C, late infantile neurologic onset, Niemann-Pick disease type C, adult neurologic onset, Niemann-Pick disease type C, juvenile neurologic onset, Niemann-Pick disease type C, severe perinatal form.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000271.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NPC1
NM_000271.5
MANE Select
c.7G>Ap.Ala3Thr
missense
Exon 1 of 25NP_000262.2O15118-1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NPC1
ENST00000269228.10
TSL:1 MANE Select
c.7G>Ap.Ala3Thr
missense
Exon 1 of 25ENSP00000269228.4O15118-1
NPC1
ENST00000897526.1
c.7G>Ap.Ala3Thr
missense
Exon 1 of 25ENSP00000567585.1
NPC1
ENST00000926494.1
c.7G>Ap.Ala3Thr
missense
Exon 1 of 25ENSP00000596553.1

Frequencies

GnomAD3 genomes
AF:
0.0000788
AC:
12
AN:
152234
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.00318
Gnomad NFE
AF:
0.000118
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000232
AC:
3
AN:
129560
AF XY:
0.00
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:
0.00
Gnomad NFE exome
AF:
0.0000626
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000190
AC:
262
AN:
1381584
Hom.:
0
Cov.:
31
AF XY:
0.000194
AC XY:
132
AN XY:
681900
show subpopulations
African (AFR)
AF:
0.000159
AC:
5
AN:
31416
American (AMR)
AF:
0.0000561
AC:
2
AN:
35644
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25114
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35658
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79066
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
34682
Middle Eastern (MID)
AF:
0.000482
AC:
2
AN:
4146
European-Non Finnish (NFE)
AF:
0.000231
AC:
249
AN:
1078172
Other (OTH)
AF:
0.0000693
AC:
4
AN:
57686
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.457
Heterozygous variant carriers
0
17
33
50
66
83
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.0000788
AC:
12
AN:
152352
Hom.:
0
Cov.:
33
AF XY:
0.000107
AC XY:
8
AN XY:
74508
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41592
American (AMR)
AF:
0.000131
AC:
2
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00342
AC:
1
AN:
292
European-Non Finnish (NFE)
AF:
0.000118
AC:
8
AN:
68028
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.000175
Hom.:
0
Bravo
AF:
0.000117
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000681
AC:
2
Asia WGS
AF:
0.000289
AC:
1
AN:
3476

ClinVar

ClinVar submissions
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
4
-
Niemann-Pick disease, type C1 (4)
-
2
-
not provided (2)
-
1
-
NPC1-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Uncertain
0.042
T
BayesDel_noAF
Uncertain
0.020
CADD
Benign
16
DANN
Uncertain
0.99
DEOGEN2
Benign
0.27
T
Eigen
Benign
-0.81
Eigen_PC
Benign
-0.81
FATHMM_MKL
Benign
0.33
N
LIST_S2
Benign
0.52
T
M_CAP
Uncertain
0.16
D
MetaRNN
Uncertain
0.72
D
MetaSVM
Benign
-0.31
T
MutationAssessor
Benign
1.5
L
PhyloP100
0.60
PrimateAI
Uncertain
0.67
T
PROVEAN
Benign
-0.60
N
REVEL
Uncertain
0.54
Sift
Benign
0.056
T
Sift4G
Benign
0.61
T
Polyphen
0.016
B
Vest4
0.66
MutPred
0.67
Gain of glycosylation at A3 (P = 0.01)
MVP
0.74
MPC
0.25
ClinPred
0.12
T
GERP RS
2.8
PromoterAI
-0.0048
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.063
gMVP
0.72
Mutation Taster
=32/68
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: rs752896980; hg19: chr18-21166301; API