rs3732557

Positions:

• chr3-149163886-C-G
• chr3-149163886-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_032383.5(HPS3):​c.2526C>G​(p.His842Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000701 in 1,427,302 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: HPS3 NM_032383.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.484

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]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.05740732).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HPS3	NM_032383.5	c.2526C>G	p.His842Gln	missense_variant	14/17	ENST00000296051.7	NP_115759.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HPS3	ENST00000296051.7	c.2526C>G	p.His842Gln	missense_variant	14/17	1	NM_032383.5	ENSP00000296051	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 7.01e-7 AC: 1 AN: 1427302 Hom.: 0 Cov.: 27 AF XY: 0.00 AC XY: 0 AN XY: 711944

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 01, 2021

This sequence change replaces histidine with glutamine at codon 842 of the HPS3 protein (p.His842Gln). The histidine residue is weakly conserved and there is a small physicochemical difference between histidine and glutamine. This variant is not present in population databases (ExAC 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 missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.60
CADD	Benign	5.3
DANN	Benign	0.64
DEOGEN2	Benign	0.094	T;T
Eigen	Benign	-1.2
Eigen_PC	Benign	-1.3
FATHMM_MKL	Benign	0.063	N
LIST_S2	Benign	0.69	T;T
M_CAP	Benign	0.035	D
MetaRNN	Benign	0.057	T;T
MetaSVM	Benign	-0.94	T
MutationAssessor	Benign	1.1	L;.
MutationTaster	Benign	1.0	P;P
PrimateAI	Benign	0.29	T
PROVEAN	Benign	0.060	N;N
REVEL	Benign	0.018
Sift	Benign	0.31	T;T
Sift4G	Benign	0.25	T;T
Polyphen		0.12	B;B
Vest4		0.14
MutPred		0.38		Loss of glycosylation at S846 (P = 0.0585);.;
MVP		0.42
MPC		0.19
ClinPred		0.17	T
GERP RS		-2.1
Varity_R		0.025
gMVP		0.093

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.12		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: rs3732557; hg19: chr3-148881673;