chr3-149162681-GTTTTTAAGGTGC-G

Variant names:

• chr3-149162681-GTTTTTAAGGTGC-G
• NM_032383.5:c.2293-5_2299delTTAAGGTGCTTT

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PP5_Moderate

The NM_032383.5(HPS3):​c.2293-5_2299delTTAAGGTGCTTT​(p.Cys767fs) variant causes a frameshift, splice acceptor, splice region, intron change. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Likely pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: HPS3 NM_032383.5 frameshift, splice_acceptor, splice_region, intron
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.01
• Publications: 0 publications found

Genes affected

HPS3 (HGNC:15597): (HPS3 biogenesis of lysosomal organelles complex 2 subunit 1) This gene encodes a protein containing a potential clathrin-binding motif, consensus dileucine signals, and tyrosine-based sorting signals for targeting to vesicles of lysosomal lineage. The encoded protein may play a role in organelle biogenesis associated with melanosomes, platelet dense granules, and lysosomes. Mutations in this gene are associated with Hermansky-Pudlak syndrome type 3. [provided by RefSeq, Apr 2015]

CP (HGNC:2295): (ceruloplasmin) The protein encoded by this gene is a metalloprotein that binds most of the copper in plasma and is involved in the peroxidation of Fe(II)transferrin to Fe(III) transferrin. Mutations in this gene cause aceruloplasminemia, which results in iron accumulation and tissue damage, and is associated with diabetes and neurologic abnormalities. Two transcript variants, one protein-coding and the other not protein-coding, have been found for this gene. [provided by RefSeq, Feb 2012]

CP Gene-Disease associations (from GenCC):

• aceruloplasminemia

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
• disorder of iron metabolism and transport

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 3-149162681-GTTTTTAAGGTGC-G is Pathogenic according to our data. Variant chr3-149162681-GTTTTTAAGGTGC-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2036321.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HPS3	NM_032383.5	c.2293-5_2299delTTAAGGTGCTTT	p.Cys767fs	frameshift_variant, splice_acceptor_variant, splice_region_variant, intron_variant	Exon 13 of 17	ENST00000296051.7	NP_115759.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HPS3	ENST00000296051.7	c.2293-5_2299delTTAAGGTGCTTT	p.Cys767fs	frameshift_variant, splice_acceptor_variant, splice_region_variant, intron_variant	Exon 13 of 17	1	NM_032383.5	ENSP00000296051.2

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Oct 20, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant results in the deletion of part of exon 13 (c.2293-5_2299del) of the HPS3 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in HPS3 are known to be pathogenic (PMID: 11590544). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with HPS3-related conditions. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		6.0

Splicing

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

Other links and lift over

hg19: chr3-148880468;