10-71816867-C-G

Variant names:

• chr10-71816867-C-G
• rs549402343
• NM_002778.4:c.*574G>C

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_002778.4(PSAP):​c.*574G>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000117 in 188,572 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00011 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00014 (0 hom.)
• Consequence: PSAP NM_002778.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:4
• Conservation: PhyloP100: -0.0100
• Publications: 0 publications found

Genes affected

PSAP (HGNC:9498): (prosaposin) This gene encodes a highly conserved preproprotein that is proteolytically processed to generate four main cleavage products including saposins A, B, C, and D. Each domain of the precursor protein is approximately 80 amino acid residues long with nearly identical placement of cysteine residues and glycosylation sites. Saposins A-D localize primarily to the lysosomal compartment where they facilitate the catabolism of glycosphingolipids with short oligosaccharide groups. The precursor protein exists both as a secretory protein and as an integral membrane protein and has neurotrophic activities. Mutations in this gene have been associated with Gaucher disease and metachromatic leukodystrophy. Alternative splicing results in multiple transcript variants, at least one of which encodes an isoform that is proteolytically processed. [provided by RefSeq, Feb 2016]

PSAP Gene-Disease associations (from GenCC):

• combined PSAP deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, ClinGen, Labcorp Genetics (formerly Invitae)
• Gaucher disease due to saposin C deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
• Krabbe disease due to saposin A deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen, G2P
• metachromatic leukodystrophy due to saposin B deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
• Parkinson disease 24, autosomal dominant, susceptibility to

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.76).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PSAP	NM_002778.4	c.*574G>C		3_prime_UTR_variant	Exon 14 of 14	ENST00000394936.8	NP_002769.1
PSAP	NM_001042465.3	c.*574G>C		3_prime_UTR_variant	Exon 15 of 15		NP_001035930.1
PSAP	NM_001042466.3	c.*574G>C		3_prime_UTR_variant	Exon 15 of 15		NP_001035931.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PSAP	ENST00000394936.8	c.*574G>C		3_prime_UTR_variant	Exon 14 of 14	1	NM_002778.4	ENSP00000378394.3

Frequencies

GnomAD3 genomes AF: 0.000112 AC: 17 AN: 152256 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000577

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000162

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000138 AC: 5 AN: 36198 Hom.: 0 Cov.: 0 AF XY: 0.000104 AC XY: 2 AN XY: 19294

African (AFR) AF: 0.00 AC: 0 AN: 1434

American (AMR) AF: 0.00 AC: 0 AN: 3462

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 668

East Asian (EAS) AF: 0.000389 AC: 1 AN: 2572

South Asian (SAS) AF: 0.00 AC: 0 AN: 5730

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 1184

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 102

European-Non Finnish (NFE) AF: 0.000206 AC: 4 AN: 19444

Other (OTH) AF: 0.00 AC: 0 AN: 1602

GnomAD4 genome AF: 0.000112 AC: 17 AN: 152374 Hom.: 0 Cov.: 33 AF XY: 0.000107 AC XY: 8 AN XY: 74506

African (AFR) AF: 0.0000240 AC: 1 AN: 41596

American (AMR) AF: 0.000131 AC: 2 AN: 15304

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.000578 AC: 3 AN: 5190

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10622

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.000162 AC: 11 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.000142 Hom.: 0

Bravo AF: 0.0000604

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, single submitter

Submissions by phenotype

Gaucher disease due to saposin C deficiency Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Combined PSAP deficiency Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Krabbe disease due to saposin A deficiency Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Sphingolipid activator protein 1 deficiency Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.76
CADD	Benign	4.9
DANN	Benign	0.72
PhyloP100		-0.010
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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: rs549402343; hg19: chr10-73576624;