rs146874573

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_000271.5(NPC1):​c.2257G>A​(p.Val753Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00021 in 1,614,112 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00021 ( 0 hom. )

Consequence

NPC1
NM_000271.5 missense

Scores

2
17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: -0.727

Publications

6 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_benign. 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.
BP4
Computational evidence support a benign effect (MetaRNN=0.14287668).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NPC1NM_000271.5 linkc.2257G>A p.Val753Met missense_variant Exon 15 of 25 ENST00000269228.10 NP_000262.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NPC1ENST00000269228.10 linkc.2257G>A p.Val753Met missense_variant Exon 15 of 25 1 NM_000271.5 ENSP00000269228.4 O15118-1
NPC1ENST00000591051.1 linkc.1333G>A p.Val445Met missense_variant Exon 8 of 18 2 ENSP00000467636.1 K7EQ23
NPC1ENST00000540608.5 linkn.2171G>A non_coding_transcript_exon_variant Exon 13 of 16 2
NPC1ENST00000586718.1 linkn.-50G>A upstream_gene_variant 3

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152222
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000121
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:
0.000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000191
AC:
48
AN:
251422
AF XY:
0.000199
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.000378
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000215
AC:
314
AN:
1461890
Hom.:
0
Cov.:
32
AF XY:
0.000227
AC XY:
165
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000812
AC:
7
AN:
86256
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53420
Middle Eastern (MID)
AF:
0.000520
AC:
3
AN:
5768
European-Non Finnish (NFE)
AF:
0.000259
AC:
288
AN:
1112010
Other (OTH)
AF:
0.000149
AC:
9
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
Heterozygous variant carriers
0
20
40
60
80
100
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:
0.000164
AC:
25
AN:
152222
Hom.:
0
Cov.:
32
AF XY:
0.000215
AC XY:
16
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.000121
AC:
5
AN:
41456
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000294
AC:
20
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.000417
Hom.:
0
Bravo
AF:
0.000132
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000148
AC:
18
EpiCase
AF:
0.000491
EpiControl
AF:
0.000533

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
Mar 19, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 29, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 26, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 33990640, 24767253, 25764212, 37251532, 33624863) -

Niemann-Pick disease, type C1 Uncertain:1Benign:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

NPC1-related disorder Uncertain:1
Aug 20, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The NPC1 c.2257G>A variant is predicted to result in the amino acid substitution p.Val753Met. This variant has not been reported in an individual with ataxia and assessed as a variant of unknown significance (Vural et al. 2021. PubMed ID: 33624863). This variant is reported in 0.039% of alleles in individuals of European (Non-Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.087
BayesDel_addAF
Benign
-0.35
T
BayesDel_noAF
Benign
-0.40
CADD
Benign
0.029
DANN
Benign
0.89
DEOGEN2
Uncertain
0.59
D
Eigen
Benign
-1.5
Eigen_PC
Benign
-1.7
FATHMM_MKL
Benign
0.057
N
LIST_S2
Benign
0.66
T
M_CAP
Benign
0.046
D
MetaRNN
Benign
0.14
T
MetaSVM
Benign
-0.34
T
MutationAssessor
Benign
1.3
L
PhyloP100
-0.73
PrimateAI
Benign
0.27
T
PROVEAN
Benign
-0.13
N
REVEL
Uncertain
0.37
Sift
Benign
0.065
T
Sift4G
Benign
0.10
T
Polyphen
0.64
P
Vest4
0.22
MVP
0.41
MPC
0.27
ClinPred
0.028
T
GERP RS
-12
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.037
gMVP
0.13
Mutation Taster
=92/8
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs146874573; hg19: chr18-21121386; COSMIC: COSV99341696; COSMIC: COSV99341696; API