chr10-71828084-G-A

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM1PP3PP5_Very_Strong

The NM_002778.4(PSAP):​c.650C>T​(p.Thr217Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000136 in 1,614,056 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T217S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

PSAP
NM_002778.4 missense

Scores

3
14
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 4.31

Publications

5 publications found
Variant links:
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)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 3 uncertain in NM_002778.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.778
PP5
Variant 10-71828084-G-A is Pathogenic according to our data. Variant chr10-71828084-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 13361.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PSAPNM_002778.4 linkc.650C>T p.Thr217Ile missense_variant Exon 6 of 14 ENST00000394936.8 NP_002769.1 P07602-1A0A024QZQ2
PSAPNM_001042465.3 linkc.650C>T p.Thr217Ile missense_variant Exon 6 of 15 NP_001035930.1 P07602-3
PSAPNM_001042466.3 linkc.650C>T p.Thr217Ile missense_variant Exon 6 of 15 NP_001035931.1 P07602-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PSAPENST00000394936.8 linkc.650C>T p.Thr217Ile missense_variant Exon 6 of 14 1 NM_002778.4 ENSP00000378394.3 P07602-1
PSAPENST00000633965.1 linkc.50C>T p.Thr17Ile missense_variant Exon 1 of 6 5 ENSP00000488331.1 A0A0J9YXB8

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152164
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000755
AC:
19
AN:
251494
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000520
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000137
AC:
20
AN:
1461892
Hom.:
0
Cov.:
32
AF XY:
0.00000825
AC XY:
6
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000425
AC:
19
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112010
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
2
3
5
6
8
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152164
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74338
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41428
American (AMR)
AF:
0.000131
AC:
2
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000508
Hom.:
0
Bravo
AF:
0.0000416
ExAC
AF:
0.0000494
AC:
6

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Feb 26, 2018
Eurofins Ntd Llc (ga)
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 16, 2023
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 2320574, 19167329) -

Sphingolipid activator protein 1 deficiency Pathogenic:2
Feb 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 217 of the PSAP protein (p.Thr217Ile). This variant is present in population databases (rs121918103, gnomAD 0.06%). This missense change has been observed in individuals with saposin deficiency (PMID: 2302219, 2320574; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 13361). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PSAP protein function with a positive predictive value of 80%. For these reasons, this variant has been classified as Pathogenic. -

Apr 01, 1990
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Inborn genetic diseases Pathogenic:1
Sep 25, 2017
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sphingolipid activator protein 1 deficiency;C1864651:Gaucher disease due to saposin C deficiency;C2673266:Krabbe disease due to saposin A deficiency;C2673635:Combined PSAP deficiency;C5561969:Parkinson disease 24, autosomal dominant, susceptibility to Pathogenic:1
Jan 19, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.53
BayesDel_addAF
Benign
-0.039
T
BayesDel_noAF
Uncertain
0.060
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.91
D;D
Eigen
Uncertain
0.42
Eigen_PC
Uncertain
0.37
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.93
D;D
M_CAP
Uncertain
0.28
D
MetaRNN
Pathogenic
0.78
D;D
MetaSVM
Uncertain
0.56
D
MutationAssessor
Uncertain
2.6
M;.
PhyloP100
4.3
PrimateAI
Uncertain
0.49
T
PROVEAN
Uncertain
-3.9
D;D
REVEL
Pathogenic
0.74
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.0030
D;D
Polyphen
0.94
P;.
Vest4
0.53
MutPred
0.80
Gain of helix (P = 0.0496);Gain of helix (P = 0.0496);
MVP
0.69
MPC
0.21
ClinPred
0.50
T
GERP RS
2.6
PromoterAI
0.054
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.77
gMVP
0.57
Mutation Taster
=5/95
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs121918103; hg19: chr10-73587841; COSMIC: COSV67550782; API