rs377130051
Variant summary
Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_000271.5(NPC1):c.1819C>T(p.Arg607*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000124 in 1,612,268 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.
Frequency
Consequence
NM_000271.5 stop_gained
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Pathogenic. Variant got 18 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
NPC1 | NM_000271.5 | c.1819C>T | p.Arg607* | stop_gained | Exon 12 of 25 | ENST00000269228.10 | NP_000262.2 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
NPC1 | ENST00000269228.10 | c.1819C>T | p.Arg607* | stop_gained | Exon 12 of 25 | 1 | NM_000271.5 | ENSP00000269228.4 | ||
NPC1 | ENST00000591051.1 | c.895C>T | p.Arg299* | stop_gained | Exon 5 of 18 | 2 | ENSP00000467636.1 | |||
NPC1 | ENST00000540608.5 | n.1733C>T | non_coding_transcript_exon_variant | Exon 10 of 16 | 2 |
Frequencies
GnomAD3 genomes AF: 0.00000658 AC: 1AN: 152040Hom.: 0 Cov.: 32
GnomAD4 exome AF: 6.85e-7 AC: 1AN: 1460228Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0AN XY: 726554
GnomAD4 genome AF: 0.00000658 AC: 1AN: 152040Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74262
ClinVar
Submissions by phenotype
Niemann-Pick disease, type C1 Pathogenic:3
This sequence change creates a premature translational stop signal (p.Arg607*) in the NPC1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in NPC1 are known to be pathogenic (PMID: 9211850). This variant is present in population databases (no rsID available, gnomAD 0.1%). This premature translational stop signal has been observed in individual(s) with Niemann-Pick type C (PMID: 11754101, 32138288). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 265495). For these reasons, this variant has been classified as Pathogenic. -
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A homozygous nonsense variant in NPC1 gene that results in a stop codon and premature truncation of the protein at codon 607 was detected. This variant has not been reported in the 1000 genomes and has a MAF of 0.0032% in the gnomAD databases. The in-silico prediction of the variant is damaging by MutationTaster2 and DANN. In summary, the variant meets our criteria to be classified as pathogenic -
Niemann-Pick disease, type C Pathogenic:1
Variant summary: The c.1819C>T (p.Arg607*) variant in NPC1 gene is a nonsense change that results in the loss of the 677 amino acids of the protein (~52%). This change is predicted to cause loss of normal protein function through protein truncation or nonsense-mediated mRNA decay and truncated protein that would be translated from this allele was not detected by western blot (Zampieri, 2013). The variant is absent from in the large control population dataset of ExAC (121384 chrs tested). The variant has been identified in compound heterozygosity with known pathogenic alleles in several affected individuals presented with the classical biochemical phenotype NPC-1 characterized by massive lysosomal/ LE accumulation of unesterified cholesterol in cultured fibroblasts. Taken together, the variant was classified as Pathogenic. -
Inborn genetic diseases Pathogenic:1
The c.1819C>T (p.R607*) alteration, located in coding exon 12 of the NPC1 gene, results from a C to T substitution at nucleotide position 1819. This changes the amino acid from an arginine (R) to a stop codon at amino acid position 607. This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. Based on data from the Genome Aggregation Database (gnomAD) database, the NPC1 c.1819C>T alteration was observed in 0.003% (1/31,382) of total alleles studied, with a frequency of 0.12% (1/848) in the Latino subpopulation. This alteration has been reported in a patient with Niemann-Pick type C based on filipin staining of cholesterol and bone marrow cytology (Bauer, 2002). Parental testing confirmed that the alteration was in trans with a >23 kb deletion in NPC1. Based on the available evidence, this alteration is classified as pathogenic. -
not provided Pathogenic:1
The R607X pathogenic variant in the NPC1 gene has been reported previously in association with Niemann-Pick Disease Type C, in an affected individual who was compound heterozygous for the R607X pathogenic variant and another variant (Bauer et al., 2002). This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The R607X variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. We interpret R607X as a pathogenic variant. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at