rs1181604094

Variant names:

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PP2PP3_Moderate

The NM_000271.5(NPC1):c.2597T>C(p.Met866Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000692 in 1,444,740 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M866I) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

NPC1
NM_000271.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 9.09

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 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM1

In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 uncertain in NM_000271.5

PM2

Very rare variant in population databases, with high coverage;

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, juvenile neurologic onset, Niemann-Pick disease type C, severe early infantile neurologic onset, Niemann-Pick disease type C, severe perinatal form, Niemann-Pick disease type C, adult neurologic onset, Niemann-Pick disease type C, late infantile neurologic onset.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.934

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NPC1	NM_000271.5 link	c.2597T>C	p.Met866Thr	missense_variant	Exon 17 of 25	ENST00000269228.10	NP_000262.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
NPC1	ENST00000269228.10 link	c.2597T>C	p.Met866Thr	missense_variant	Exon 17 of 25	1	NM_000271.5	ENSP00000269228.4	O15118-1
NPC1	ENST00000591051.1 link	c.1673T>C	p.Met558Thr	missense_variant	Exon 10 of 18	2		ENSP00000467636.1	K7EQ23
NPC1	ENST00000540608.5 link	n.2511T>C		non_coding_transcript_exon_variant	Exon 15 of 16	2
NPC1	ENST00000586718.1 link	n.388T>C		non_coding_transcript_exon_variant	Exon 2 of 3	3

Frequencies

GnomAD3 genomes

Cov.:

GnomAD2 exomes

AF:

0.00000401

AC:

AN:

249142

AF XY:

0.00

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000545

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.92e-7

AC:

AN:

1444740

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

719526

show subpopulations

Gnomad4 AFR exome

AF:

0.00

AC:

AN:

33154

Gnomad4 AMR exome

AF:

0.00

AC:

AN:

44624

Gnomad4 ASJ exome

AF:

0.00

AC:

AN:

26054

Gnomad4 EAS exome

AF:

0.00

AC:

AN:

39594

Gnomad4 SAS exome

AF:

0.00

AC:

AN:

85538

Gnomad4 FIN exome

AF:

0.00

AC:

AN:

52560

Gnomad4 NFE exome

AF:

9.11e-7

AC:

AN:

1097668

Gnomad4 Remaining exome

AF:

0.00

AC:

AN:

59798

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Exome Het

Variant carriers

<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

Cov.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Niemann-Pick disease, type C1

Uncertain:2

Feb 23, 2023

3billion

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.85; 3Cnet: 0.92). Same nucleotide change resulting in same amino acid change has been previously reported to be associated with NPC1 related disorder (PMID: 26981555). However, the evidence of pathogenicity is insufficient at this time. Therefore, this variant is classified as VUS according to the recommendation of ACMG/AMP guideline. -

Mar 24, 2018

Counsyl

Significance:Uncertain significance

Review Status:no assertion criteria provided

Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.70

BayesDel_addAF

Pathogenic

0.43

BayesDel_noAF

Pathogenic

0.39

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.83

Eigen

Pathogenic

0.87

Eigen_PC

Pathogenic

0.79

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.95

M_CAP

Pathogenic

0.50

MetaRNN

Pathogenic

0.93

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.6

PrimateAI

Uncertain

0.60

PROVEAN

Pathogenic

-5.5

REVEL

Pathogenic

0.85

Sift

Uncertain

0.0010

Sift4G

Uncertain

0.0020

Polyphen

1.0

Vest4

0.94

MutPred

0.66

Loss of stability (P = 0.0361);

MVP

0.96

MPC

0.58

ClinPred

0.98

GERP RS

6.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.92

gMVP

0.88

Mutation Taster

=2/98

disease causing

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.090

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over