rs281865081

chr10-98427239-GC-Gchr10-98427239-GC-GCC

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000195.5(HPS1):c.962del(p.Gly321AlafsTer10) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000258 in 1,550,614 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G321G) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: HPS1 NM_000195.5 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 0.920

Genes affected

HPS1 (HGNC:5163): (HPS1 biogenesis of lysosomal organelles complex 3 subunit 1) This gene encodes a protein that may play a role in organelle biogenesis associated with melanosomes, platelet dense granules, and lysosomes. The encoded protein is a component of three different protein complexes termed biogenesis of lysosome-related organelles complex (BLOC)-3, BLOC4, and BLOC5. Mutations in this gene are associated with Hermansky-Pudlak syndrome type 1. Alternative splicing results in multiple transcript variants. A pseudogene related to this gene is located on chromosome 22. [provided by RefSeq, Aug 2015]

ACMG classification

Verdict is Pathogenic. Variant got 18 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 10-98427239-GC-G is Pathogenic according to our data. Variant chr10-98427239-GC-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1341380.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HPS1	NM_000195.5	c.962del	p.Gly321AlafsTer10	frameshift_variant	11/20	ENST00000361490.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HPS1	ENST00000361490.9	c.962del	p.Gly321AlafsTer10	frameshift_variant	11/20	1	NM_000195.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152216 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000215 AC: 3 AN: 1398398 Hom.: 0 Cov.: 30 AF XY: 0.00000145 AC XY: 1 AN XY: 689782

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000126

Gnomad4 FIN exome AF: 0.0000204

Gnomad4 NFE exome AF: 9.27e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152216 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74360

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Jul 06, 2021

For these reasons, this variant has been classified as Pathogenic. This sequence change creates a premature translational stop signal (p.Gly321Alafs*10) in the HPS1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HPS1 are known to be pathogenic (PMID: 12442288, 16185271). This variant is not present in population databases (ExAC no frequency). ClinVar contains an entry for this variant (Variation ID: 21110). This variant is also known as G321delG. This premature translational stop signal has been observed in individual(s) with Hermansky-Pudlak syndrome (PMID: 9497254). -

Hermansky-Pudlak syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

curation

Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard

Nov 29, 2021

The p.Gly321fs variant in HPS1 has been reported in 1 individual, in the compound heterozygous state, with Hermansky-Pudlak syndrome (PMID: 9497254), and has been identified in 0.006% (1/15402) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs606231156). Although this variant has been seen in the general population in a heterozygous state, its frequency is low enough to be consistent with a recessive carrier frequency. It is of note that this variant occurs in a homopolymer repeat, which could indicate that it exists as an artifact from sequencing. However, disease-causing variants have been reported in homopolymer regions, so this is not enough to rule out a pathogenic role. This variant has also been reported in ClinVar (Variation ID#: 21110) and has been interpreted as pathogenic by GeneReviews. This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 321 and leads to a premature termination codon 10 amino acids downstream. This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the HPS1 gene is an established disease mechanism in autosomal recessive Hermansky-Pudlak syndrome. In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic for autosomal recessive Hermansky-Pudlak syndrome. ACMG/AMP Criteria applied: PM3_supporting, PM2_supporting, PVS1 (Richards 2015). -

Hermansky-Pudlak syndrome 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Sep 14, 2023

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

Other links and lift over

dbSNP: rs281865081; hg19: chr10-100186996;