rs200813294

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_000310.4(PPT1):​c.802C>T​(p.Arg268Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000118 in 1,614,070 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R268H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000085 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

PPT1
NM_000310.4 missense

Scores

10
5
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 9.72

Publications

2 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: Uncertain_significance. The variant received 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.899

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PPT1NM_000310.4 linkc.802C>T p.Arg268Cys missense_variant Exon 9 of 9 ENST00000642050.2 NP_000301.1
PPT1NM_001363695.2 linkc.730C>T p.Arg244Cys missense_variant Exon 8 of 8 NP_001350624.1
PPT1NM_001142604.2 linkc.493C>T p.Arg165Cys missense_variant Exon 6 of 6 NP_001136076.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PPT1ENST00000642050.2 linkc.802C>T p.Arg268Cys missense_variant Exon 9 of 9 NM_000310.4 ENSP00000493153.1

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152134
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.000132
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000796
AC:
20
AN:
251366
AF XY:
0.0000810
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000167
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000121
AC:
177
AN:
1461818
Hom.:
0
Cov.:
31
AF XY:
0.000125
AC XY:
91
AN XY:
727210
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53380
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000154
AC:
171
AN:
1111980
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
12
24
36
48
60
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000854
AC:
13
AN:
152252
Hom.:
0
Cov.:
32
AF XY:
0.0000940
AC XY:
7
AN XY:
74460
show subpopulations
African (AFR)
AF:
0.0000482
AC:
2
AN:
41532
American (AMR)
AF:
0.000131
AC:
2
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
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:
294
European-Non Finnish (NFE)
AF:
0.000132
AC:
9
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.443
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000582
Hom.:
0
Bravo
AF:
0.0000869
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000123
AC:
15
EpiCase
AF:
0.000273
EpiControl
AF:
0.000296

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis 1 Uncertain:3
Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 13, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 268 of the PPT1 protein (p.Arg268Cys). This variant is present in population databases (rs200813294, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with PPT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 449662). 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. 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. -

Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Nov 12, 2018
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R268C variant (also known as c.802C>T), located in coding exon 9 of the PPT1 gene, results from a C to T substitution at nucleotide position 802. The arginine at codon 268 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1
Jan 06, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 25741868) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.18
BayesDel_addAF
Pathogenic
0.27
D
BayesDel_noAF
Pathogenic
0.43
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.97
D;.;.;.;.;.;.
Eigen
Uncertain
0.55
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.94
.;D;D;D;D;D;D
M_CAP
Pathogenic
0.35
D
MetaRNN
Pathogenic
0.90
D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
M;.;.;.;.;.;.
PhyloP100
9.7
PrimateAI
Benign
0.47
T
PROVEAN
Pathogenic
-4.7
.;.;D;.;.;D;.
REVEL
Pathogenic
0.82
Sift
Benign
0.075
.;.;T;.;.;T;.
Sift4G
Uncertain
0.0020
.;.;D;.;.;D;.
Polyphen
1.0
D;.;.;.;.;D;.
Vest4
0.65, 0.58
MVP
0.97
MPC
0.23
ClinPred
0.87
D
GERP RS
4.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.76
gMVP
0.52
Mutation Taster
=37/63
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: rs200813294; hg19: chr1-40539852; COSMIC: COSV100472297; COSMIC: COSV100472297; API