NM_000271.5:c.2873G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP2PP3_ModeratePP5

The NM_000271.5(NPC1):​c.2873G>A​(p.Arg958Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,842 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. R958R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

NPC1
NM_000271.5 missense

Scores

6
11
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:1

Conservation

PhyloP100: 7.75

Publications

11 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, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Myriad Women’s Health
  • 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: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 uncertain in NM_000271.5
PM2
Very rare variant in population databases, with high coverage;
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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.931
PP5
Variant 18-23539393-C-T is Pathogenic according to our data. Variant chr18-23539393-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2968.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NPC1NM_000271.5 linkc.2873G>A p.Arg958Gln missense_variant Exon 19 of 25 ENST00000269228.10 NP_000262.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NPC1ENST00000269228.10 linkc.2873G>A p.Arg958Gln missense_variant Exon 19 of 25 1 NM_000271.5 ENSP00000269228.4 O15118-1
NPC1ENST00000591051.1 linkc.1949G>A p.Arg650Gln missense_variant Exon 12 of 18 2 ENSP00000467636.1 K7EQ23
NPC1ENST00000591075.1 linkn.506G>A non_coding_transcript_exon_variant Exon 1 of 3 4

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152198
Hom.:
0
Cov.:
33
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251178
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000616
AC:
9
AN:
1461644
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727096
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.0000447
AC:
2
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26116
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86174
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111882
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.453
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

Exome 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
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152198
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.675
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000194
Hom.:
0
Bravo
AF:
0.0000151
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:3Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Niemann-Pick disease, type C1 Pathogenic:3Uncertain:1
Aug 08, 2022
Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A compound heterozygous missense variation in exon 19 of the NPC1 gene that results in the amino acid substitution of Glutamine for Arginine at codon 958 was detected. The observed variant c.2873G>A (p.Arg958Gln) has not been reported in the 1000 genomes and has a MAF of 0.0002% and 0.001% in the gnomAD databases . The in silico prediction of the variant are possibly damaging by Mutation Taster, DANN, LRT, and SIFT. The reference codon is conserved across species. -

Nov 16, 2021
Myriad Genetics, Inc.
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

NM_000271.4(NPC1):c.2873G>A(R958Q) is a missense variant classified as a variant of uncertain significance in the context of Niemann-Pick disease type C1. R958Q has been observed in cases with relevant disease (PMID: 11349231, 17160617, 23433426). Functional assessments of this variant are available in the literature (PMID: 28193631, 31699992). R958Q has been observed in population frequency databases (gnomAD: EAS 0.01%). In summary, there is insufficient evidence to classify NM_000271.4(NPC1):c.2873G>A(R958Q) as pathogenic or benign. Please note: this variant was assessed in the context of healthy population screening. -

Jun 01, 2001
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

May 22, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 958 of the NPC1 protein (p.Arg958Gln). This variant is present in population databases (rs120074132, gnomAD 0.006%). This missense change has been observed in individual(s) with Niemann-Pick disease type C (PMID: 11349231). ClinVar contains an entry for this variant (Variation ID: 2968). 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 with a positive predictive value of 95%. This variant disrupts the p.Arg958 amino acid residue in NPC1. Other variant(s) that disrupt this residue have been observed in individuals with NPC1-related conditions (PMID: 11754101, 35086560), which suggests that this may be a clinically significant amino acid residue. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.26
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.49
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.79
D
Eigen
Uncertain
0.58
Eigen_PC
Uncertain
0.41
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Uncertain
0.97
D
M_CAP
Uncertain
0.25
D
MetaRNN
Pathogenic
0.93
D
MetaSVM
Pathogenic
0.94
D
MutationAssessor
Pathogenic
3.5
M
PhyloP100
7.7
PrimateAI
Uncertain
0.53
T
PROVEAN
Uncertain
-3.3
D
REVEL
Pathogenic
0.69
Sift
Uncertain
0.011
D
Sift4G
Uncertain
0.023
D
Polyphen
1.0
D
Vest4
0.91
MVP
0.93
MPC
0.98
ClinPred
0.93
D
GERP RS
5.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.58
gMVP
0.91
Mutation Taster
=15/85
disease causing (ClinVar)

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: rs120074132; hg19: chr18-21119357; COSMIC: COSV52580931; COSMIC: COSV52580931; API