chr22-26465579-A-C

Variant names:

• chr22-26465579-A-C
• rs3213583
• NM_022081.6:c.707-28T>G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_022081.6(HPS4):​c.707-28T>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. There are indicators that this mutation may affect the branch point..

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: HPS4 NM_022081.6 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.491
• Publications: 9 publications found

Genes affected

HPS4 (HGNC:15844): (HPS4 biogenesis of lysosomal organelles complex 3 subunit 2) This gene encodes a protein component of biogenesis of lysosome-related organelles complexes (BLOC). BLOC complexes are important for the formation of endosomal-lysosomal organelles such as melanosomes and platelet dense granules. Mutations in this gene result in subtype 4 of Hermansky-Pudlak syndrome, a form of albinism. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2012]

HPS4 Gene-Disease associations (from GenCC):

• Hermansky-Pudlak syndrome 4

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: G2P, ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics
• Hermansky-Pudlak syndrome with pulmonary fibrosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: This position, referring to a specific DNA site, is a probable branch point but is likely benign (scored 3 / 10, using the threshold of <=3). The score ranges from 0 to 10, with values ≤3 considered benign and >5 classified as pathogenic. Computational evidence support a benign effect (BayesDel_noAF=-0.82).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HPS4	NM_022081.6	c.707-28T>G		intron_variant	Intron 9 of 13	ENST00000398145.7	NP_071364.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HPS4	ENST00000398145.7	c.707-28T>G		intron_variant	Intron 9 of 13	1	NM_022081.6	ENSP00000381213.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1430964 Hom.: 0 Cov.: 24 AF XY: 0.00 AC XY: 0 AN XY: 714046

African (AFR) AF: 0.00 AC: 0 AN: 32834

American (AMR) AF: 0.00 AC: 0 AN: 44668

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25948

East Asian (EAS) AF: 0.00 AC: 0 AN: 39492

South Asian (SAS) AF: 0.00 AC: 0 AN: 85598

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52676

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5686

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1084642

Other (OTH) AF: 0.00 AC: 0 AN: 59420

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	12
DANN	Benign	0.66
PhyloP100		0.49
BranchPoint Hunter		3.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs3213583; hg19: chr22-26861545;