rs116436235

Variant summary

Our verdict is Benign. The variant received -18 ACMG points: 0P and 18B. BP4_ModerateBP6_Very_StrongBS1BS2

The NM_000271.5(NPC1):​c.3441C>T​(p.Ile1147Ile) variant causes a synonymous change. The variant allele was found at a frequency of 0.000612 in 1,613,746 control chromosomes in the GnomAD database, including 7 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0033 ( 4 hom., cov: 32)
Exomes 𝑓: 0.00033 ( 3 hom. )

Consequence

NPC1
NM_000271.5 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8

Conservation

PhyloP100: 5.71

Publications

0 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: Benign. The variant received -18 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.29).
BP6
Variant 18-23535505-G-A is Benign according to our data. Variant chr18-23535505-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 326249.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00328 (500/152266) while in subpopulation AFR AF = 0.0115 (479/41542). AF 95% confidence interval is 0.0107. There are 4 homozygotes in GnomAd4. There are 247 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 4 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NPC1NM_000271.5 linkc.3441C>T p.Ile1147Ile synonymous_variant Exon 22 of 25 ENST00000269228.10 NP_000262.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NPC1ENST00000269228.10 linkc.3441C>T p.Ile1147Ile synonymous_variant Exon 22 of 25 1 NM_000271.5 ENSP00000269228.4 O15118-1

Frequencies

GnomAD3 genomes
AF:
0.00327
AC:
498
AN:
152148
Hom.:
4
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0115
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00105
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:
0.00
Gnomad OTH
AF:
0.00239
GnomAD2 exomes
AF:
0.000826
AC:
207
AN:
250662
AF XY:
0.000657
show subpopulations
Gnomad AFR exome
AF:
0.0112
Gnomad AMR exome
AF:
0.000406
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000882
Gnomad OTH exome
AF:
0.00114
GnomAD4 exome
AF:
0.000334
AC:
488
AN:
1461480
Hom.:
3
Cov.:
32
AF XY:
0.000279
AC XY:
203
AN XY:
727010
show subpopulations
African (AFR)
AF:
0.0122
AC:
407
AN:
33472
American (AMR)
AF:
0.000604
AC:
27
AN:
44680
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39688
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86186
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53378
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000630
AC:
7
AN:
1111804
Other (OTH)
AF:
0.000663
AC:
40
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
28
56
83
111
139
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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:
0.00328
AC:
500
AN:
152266
Hom.:
4
Cov.:
32
AF XY:
0.00332
AC XY:
247
AN XY:
74470
show subpopulations
African (AFR)
AF:
0.0115
AC:
479
AN:
41542
American (AMR)
AF:
0.00105
AC:
16
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68020
Other (OTH)
AF:
0.00237
AC:
5
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.499
Heterozygous variant carriers
0
25
51
76
102
127
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
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
Alfa
AF:
0.00144
Hom.:
2
Bravo
AF:
0.00390
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.0000594

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Niemann-Pick disease, type C1 Benign:4
Sep 03, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Jan 31, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 11, 2019
Natera, Inc.
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Benign:2
Mar 04, 2021
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Inborn genetic diseases Benign:1
Mar 30, 2022
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

NPC1-related disorder Benign:1
Sep 27, 2021
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.29
CADD
Benign
12
DANN
Benign
0.88
PhyloP100
5.7
PromoterAI
-0.022
Neutral
Mutation Taster
=13/87
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: rs116436235; hg19: chr18-21115469; API