rs756815030

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1PM2PP5

The NM_000271.5(NPC1):​c.2972_2973delAG​(p.Gln991ArgfsTer15) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000273 in 1,614,068 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. Q991Q) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

NPC1
NM_000271.5 frameshift

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:10U:1

Conservation

PhyloP100: 1.47

Publications

13 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: Pathogenic. The variant received 11 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 18-23538609-CCT-C is Pathogenic according to our data. Variant chr18-23538609-CCT-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 188932.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000271.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NPC1
NM_000271.5
MANE Select
c.2972_2973delAGp.Gln991ArgfsTer15
frameshift
Exon 20 of 25NP_000262.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NPC1
ENST00000269228.10
TSL:1 MANE Select
c.2972_2973delAGp.Gln991ArgfsTer15
frameshift
Exon 20 of 25ENSP00000269228.4
NPC1
ENST00000591051.1
TSL:2
c.2048_2049delAGp.Gln683fs
frameshift
Exon 13 of 18ENSP00000467636.1
NPC1
ENST00000591075.1
TSL:4
n.605_606delAG
non_coding_transcript_exon
Exon 2 of 3

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152200
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
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:
0.00
GnomAD2 exomes
AF:
0.0000477
AC:
12
AN:
251484
AF XY:
0.0000294
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000924
Gnomad NFE exome
AF:
0.0000527
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000294
AC:
43
AN:
1461868
Hom.:
0
AF XY:
0.0000248
AC XY:
18
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.000191
AC:
5
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.0000464
AC:
4
AN:
86258
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53414
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000207
AC:
23
AN:
1111994
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
2
4
5
7
9
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:
152200
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74372
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000227
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

ClinVar submissions as Germline

Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
5
-
-
Niemann-Pick disease, type C1 (5)
2
1
-
not provided (3)
2
-
-
Niemann-Pick disease, type C (2)
1
-
-
NPC1-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
PhyloP100
1.5
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
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: rs756815030; hg19: chr18-21118573; API