18-23535495-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_000271.5(NPC1):​c.3451G>A​(p.Ala1151Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,613,180 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

NPC1
NM_000271.5 missense

Scores

15
3
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.90
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1
In a transmembrane_region Helical (size 20) in uniprot entity NPC1_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_000271.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.991
PP5
Variant 18-23535495-C-T is Pathogenic according to our data. Variant chr18-23535495-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 568770.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
NPC1NM_000271.5 linkuse as main transcriptc.3451G>A p.Ala1151Thr missense_variant 22/25 ENST00000269228.10 NP_000262.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
NPC1ENST00000269228.10 linkuse as main transcriptc.3451G>A p.Ala1151Thr missense_variant 22/251 NM_000271.5 ENSP00000269228.4 O15118-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152130
Hom.:
0
Cov.:
32
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:
0.0000294
Gnomad OTH
AF:
0.000478
GnomAD3 exomes
AF:
0.00000400
AC:
1
AN:
250180
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135244
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 SAS exome
AF:
0.0000329
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000164
AC:
24
AN:
1461050
Hom.:
0
Cov.:
32
AF XY:
0.0000206
AC XY:
15
AN XY:
726798
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000180
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152130
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74318
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.000478
Alfa
AF:
0.00000961
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:3
Pathogenic, no assertion criteria providedclinical testingDiagnostic Laboratory, Department of Genetics, University Medical Center Groningen-- -
Likely pathogenic, no assertion criteria providedclinical testingClinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center-- -
Likely pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Aug 30, 2018- -
Niemann-Pick disease, type C1 Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 27, 2023For these reasons, this variant has been classified as Pathogenic. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt NPC1 protein function. ClinVar contains an entry for this variant (Variation ID: 568770). This missense change has been observed in individual(s) with Niemann-Pick disease type C1 (PMID: 19744920, 20718790, 27581084; Invitae). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1151 of the NPC1 protein (p.Ala1151Thr). -
Likely pathogenic, no assertion criteria providedclinical testingNatera, Inc.Oct 27, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.59
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.84
D
Eigen
Pathogenic
0.72
Eigen_PC
Uncertain
0.61
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Pathogenic
0.31
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Uncertain
0.78
D
MutationAssessor
Pathogenic
2.9
M
PrimateAI
Pathogenic
0.84
D
PROVEAN
Uncertain
-3.8
D
REVEL
Pathogenic
0.83
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.98
MutPred
0.95
Loss of helix (P = 0.2022);
MVP
0.94
MPC
0.90
ClinPred
0.98
D
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.90
gMVP
0.85

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs765729815; hg19: chr18-21115459; COSMIC: COSV52573912; COSMIC: COSV52573912; API