rs66620415

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_000271.5(NPC1):​c.1947+8G>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000298 in 1,286,700 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000090 ( 0 hom., cov: 27)
Exomes 𝑓: 0.00030 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

NPC1
NM_000271.5 splice_region, intron

Scores

2
Splicing: ADA: 0.00002131
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4

Conservation

PhyloP100: 0.0930

Publications

3 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, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Laboratory for Molecular Medicine, G2P
  • 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 -5 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.81).
BP6
Variant 18-23544952-C-G is Benign according to our data. Variant chr18-23544952-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 92705.

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

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NPC1
NM_000271.5
MANE Select
c.1947+8G>C
splice_region intron
N/ANP_000262.2O15118-1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NPC1
ENST00000269228.10
TSL:1 MANE Select
c.1947+8G>C
splice_region intron
N/AENSP00000269228.4O15118-1
NPC1
ENST00000897526.1
c.1998+8G>C
splice_region intron
N/AENSP00000567585.1
NPC1
ENST00000926494.1
c.1947+8G>C
splice_region intron
N/AENSP00000596553.1

Frequencies

GnomAD3 genomes
AF:
0.0000834
AC:
12
AN:
143812
Hom.:
0
Cov.:
27
show subpopulations
Gnomad AFR
AF:
0.0000745
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000217
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:
0.0000943
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000776
AC:
187
AN:
240878
AF XY:
0.000640
show subpopulations
Gnomad AFR exome
AF:
0.000257
Gnomad AMR exome
AF:
0.00316
Gnomad ASJ exome
AF:
0.0000999
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000942
Gnomad NFE exome
AF:
0.000722
Gnomad OTH exome
AF:
0.000340
GnomAD4 exome
AF:
0.000298
AC:
384
AN:
1286700
Hom.:
0
Cov.:
27
AF XY:
0.000281
AC XY:
182
AN XY:
646810
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000954
AC:
3
AN:
31446
American (AMR)
AF:
0.00233
AC:
98
AN:
42024
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25154
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35134
South Asian (SAS)
AF:
0.0000606
AC:
5
AN:
82450
European-Finnish (FIN)
AF:
0.0000404
AC:
2
AN:
49534
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5452
European-Non Finnish (NFE)
AF:
0.000276
AC:
265
AN:
961542
Other (OTH)
AF:
0.000204
AC:
11
AN:
53964
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.312
Heterozygous variant carriers
0
32
64
97
129
161
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
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
Data not reliable, filtered out with message: AS_VQSR
AF:
0.0000903
AC:
13
AN:
143920
Hom.:
0
Cov.:
27
AF XY:
0.0000995
AC XY:
7
AN XY:
70374
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000743
AC:
3
AN:
40402
American (AMR)
AF:
0.000289
AC:
4
AN:
13862
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3386
East Asian (EAS)
AF:
0.00
AC:
0
AN:
4930
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4356
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10222
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
290
European-Non Finnish (NFE)
AF:
0.0000943
AC:
6
AN:
63646
Other (OTH)
AF:
0.00
AC:
0
AN:
1966
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000000565882), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.346
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
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0

ClinVar

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

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.81
CADD
Benign
0.29
DANN
Benign
0.31
PhyloP100
0.093
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000021
dbscSNV1_RF
Benign
0.0
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: rs66620415; hg19: chr18-21124916; COSMIC: COSV52576070; COSMIC: COSV52576070; API