chr1-40080483-C-G

Variant summary

Our verdict is Pathogenic. The variant received 26 ACMG points: 26P and 0B. PS1_Very_StrongPM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000310.4(PPT1):​c.541G>C​(p.Val181Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,306 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 nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V181M) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PPT1
NM_000310.4 missense

Scores

10
4
5

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 7.81

Publications

26 publications found
Variant links:
Genes affected
PPT1 (HGNC:9325): (palmitoyl-protein thioesterase 1) The protein encoded by this gene is a small glycoprotein involved in the catabolism of lipid-modified proteins during lysosomal degradation. The encoded enzyme removes thioester-linked fatty acyl groups such as palmitate from cysteine residues. Defects in this gene are a cause of infantile neuronal ceroid lipofuscinosis 1 (CLN1, or INCL) and neuronal ceroid lipofuscinosis 4 (CLN4). Two transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Dec 2008]
PPT1 Gene-Disease associations (from GenCC):
  • neuronal ceroid lipofuscinosis
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • neuronal ceroid lipofuscinosis 1
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen, G2P, Orphanet, Myriad Women’s Health

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 26 ACMG points.

PS1
Transcript NM_000310.4 (PPT1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000310.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-40080483-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 188857.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.984
PP5
Variant 1-40080483-C-G is Pathogenic according to our data. Variant chr1-40080483-C-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 1072746.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
PPT1NM_000310.4 linkc.541G>C p.Val181Leu missense_variant Exon 6 of 9 ENST00000642050.2 NP_000301.1 P50897-1
PPT1NM_001363695.2 linkc.541G>C p.Val181Leu missense_variant Exon 6 of 8 NP_001350624.1
PPT1NM_001142604.2 linkc.232G>C p.Val78Leu missense_variant Exon 3 of 6 NP_001136076.1 P50897-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PPT1ENST00000642050.2 linkc.541G>C p.Val181Leu missense_variant Exon 6 of 9 NM_000310.4 ENSP00000493153.1 P50897-1

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151758
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461548
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
727112
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39686
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53372
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111762
Other (OTH)
AF:
0.00
AC:
0
AN:
60376
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000659
AC:
1
AN:
151758
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74072
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41252
American (AMR)
AF:
0.00
AC:
0
AN:
15244
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5162
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10500
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
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

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis 1 Pathogenic:2
Nov 06, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 181 of the PPT1 protein (p.Val181Leu). This variant is not present in population databases (gnomAD no frequency). A different variant (c.541G>T) giving rise to the same protein effect has been determined to be pathogenic (PMID: 10477428, 19302939, 21499717). This suggests that this variant is also likely to be causative of disease. ClinVar contains an entry for this variant (Variation ID: 1072746). 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 PPT1 protein function with a positive predictive value of 80%. This variant disrupts the p.Val181 amino acid residue in PPT1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 22387303, 23374165). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Feb 02, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
May 03, 2021
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.83
BayesDel_addAF
Pathogenic
0.54
D
BayesDel_noAF
Pathogenic
0.54
CADD
Uncertain
23
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.95
D;.;.;.;.;.;.
Eigen
Benign
0.16
Eigen_PC
Benign
0.17
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.85
.;D;D;D;D;D;D
M_CAP
Pathogenic
0.36
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.99
D
MutationAssessor
Pathogenic
3.5
M;.;.;.;.;.;.
PhyloP100
7.8
PrimateAI
Benign
0.41
T
PROVEAN
Uncertain
-2.4
.;.;.;.;.;N;.
REVEL
Pathogenic
0.80
Sift
Uncertain
0.015
.;.;.;.;.;D;.
Sift4G
Uncertain
0.023
.;.;.;.;.;D;.
Polyphen
0.098
B;.;.;.;.;P;.
Vest4
0.72
MutPred
0.93
Loss of sheet (P = 0.0315);.;.;Loss of sheet (P = 0.0315);Loss of sheet (P = 0.0315);.;.;
MVP
0.95
MPC
0.25
ClinPred
0.95
D
GERP RS
4.8
Varity_R
0.87
gMVP
0.60
Mutation Taster
=0/100
disease causing

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

Publications

Other links and lift over

dbSNP: rs148412181; hg19: chr1-40546155; API