18-23535454-T-C
Variant names: 
Variant summary
Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_StrongBP6_Very_Strong
The NM_000271.5(NPC1):c.3477+15A>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000229 in 1,572,462 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).
Frequency
 Genomes: 𝑓 0.000072   (  0   hom.,  cov: 32) 
 Exomes 𝑓:  0.000018   (  0   hom.  ) 
Consequence
 NPC1
NM_000271.5 intron
NM_000271.5 intron
Scores
 2
Clinical Significance
Conservation
 PhyloP100:  -1.38  
Publications
0 publications found 
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 C1Inheritance: 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 onsetInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- Niemann-Pick disease type C, juvenile neurologic onsetInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- Niemann-Pick disease type C, late infantile neurologic onsetInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- Niemann-Pick disease type C, severe early infantile neurologic onsetInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- Niemann-Pick disease type C, severe perinatal formInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Classification was made for transcript
Our verdict: Benign. The variant received -12 ACMG points.
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.82). 
BP6
Variant 18-23535454-T-C is Benign according to our data. Variant chr18-23535454-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 255697.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. 
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt | 
|---|---|---|---|---|---|---|---|---|
| NPC1 | NM_000271.5 | c.3477+15A>G | intron_variant | Intron 22 of 24 | ENST00000269228.10 | NP_000262.2 | 
Ensembl
Frequencies
GnomAD3 genomes  0.0000723  AC: 11AN: 152124Hom.:  0  Cov.: 32 show subpopulations 
GnomAD3 genomes 
 AF: 
AC: 
11
AN: 
152124
Hom.: 
Cov.: 
32
Gnomad AFR 
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Gnomad OTH 
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GnomAD2 exomes  AF:  0.0000210  AC: 5AN: 238378 AF XY:  0.0000233   show subpopulations 
GnomAD2 exomes 
 AF: 
AC: 
5
AN: 
238378
 AF XY: 
Gnomad AFR exome 
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Gnomad ASJ exome 
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Gnomad OTH exome 
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GnomAD4 exome  AF:  0.0000176  AC: 25AN: 1420338Hom.:  0  Cov.: 27 AF XY:  0.0000169  AC XY: 12AN XY: 708096 show subpopulations 
GnomAD4 exome 
 AF: 
AC: 
25
AN: 
1420338
Hom.: 
Cov.: 
27
 AF XY: 
AC XY: 
12
AN XY: 
708096
show subpopulations 
African (AFR) 
 AF: 
AC: 
15
AN: 
32446
American (AMR) 
 AF: 
AC: 
0
AN: 
43542
Ashkenazi Jewish (ASJ) 
 AF: 
AC: 
0
AN: 
25772
East Asian (EAS) 
 AF: 
AC: 
0
AN: 
39082
South Asian (SAS) 
 AF: 
AC: 
1
AN: 
84256
European-Finnish (FIN) 
 AF: 
AC: 
0
AN: 
52820
Middle Eastern (MID) 
 AF: 
AC: 
0
AN: 
5694
European-Non Finnish (NFE) 
 AF: 
AC: 
7
AN: 
1077716
Other (OTH) 
 AF: 
AC: 
2
AN: 
59010
 Allele Balance Distribution 
 Red line indicates average allele balance 
 Average allele balance: 0.499 
Heterozygous variant carriers
 0 
 1 
 3 
 4 
 6 
 7 
 0.00 
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 0.95 
Allele balance
Age Distribution
Exome Het
Variant carriers
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 >80 
Age
GnomAD4 genome  0.0000723  AC: 11AN: 152124Hom.:  0  Cov.: 32 AF XY:  0.0000942  AC XY: 7AN XY: 74320 show subpopulations 
GnomAD4 genome 
 AF: 
AC: 
11
AN: 
152124
Hom.: 
Cov.: 
32
 AF XY: 
AC XY: 
7
AN XY: 
74320
show subpopulations 
African (AFR) 
 AF: 
AC: 
9
AN: 
41426
American (AMR) 
 AF: 
AC: 
1
AN: 
15266
Ashkenazi Jewish (ASJ) 
 AF: 
AC: 
0
AN: 
3472
East Asian (EAS) 
 AF: 
AC: 
0
AN: 
5194
South Asian (SAS) 
 AF: 
AC: 
0
AN: 
4828
European-Finnish (FIN) 
 AF: 
AC: 
0
AN: 
10610
Middle Eastern (MID) 
 AF: 
AC: 
0
AN: 
316
European-Non Finnish (NFE) 
 AF: 
AC: 
0
AN: 
68012
Other (OTH) 
 AF: 
AC: 
1
AN: 
2088
 Allele Balance Distribution 
 Red line indicates average allele balance 
 Average allele balance: 0.489 
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 
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Age
Alfa 
 AF: 
Hom.: 
Bravo 
 AF: 
ClinVar
Significance: Likely benign 
Submissions summary: Benign:2 
Revision: criteria provided, multiple submitters, no conflicts
LINK: link 
Submissions by phenotype
not specified    Benign:1 
-
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing
- -
Niemann-Pick disease, type C1    Benign:1 
Jan 21, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing
- -
Computational scores
Source: 
Name
Calibrated prediction
Score
Prediction
 BayesDel_noAF 
 Benign 
 DANN 
 Benign 
 PhyloP100 
 RBP_binding_hub_radar 
 RBP_regulation_power_radar 
Splicing
Name
Calibrated prediction
Score
Prediction
 SpliceAI score (max) 
Details are displayed if max score is > 0.2
 Find out detailed SpliceAI scores and Pangolin per-transcript scores at 
Publications
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