chr1-40080438-G-A

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000310.4(PPT1):​c.586C>T​(p.Arg196Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000124 in 1,613,856 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. R196H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

PPT1
NM_000310.4 missense

Scores

11
5
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 4.79

Publications

1 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 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.915

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PPT1NM_000310.4 linkc.586C>T p.Arg196Cys missense_variant Exon 6 of 9 ENST00000642050.2 NP_000301.1 P50897-1
PPT1NM_001363695.2 linkc.586C>T p.Arg196Cys missense_variant Exon 6 of 8 NP_001350624.1
PPT1NM_001142604.2 linkc.277C>T p.Arg93Cys 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.586C>T p.Arg196Cys missense_variant Exon 6 of 9 NM_000310.4 ENSP00000493153.1 P50897-1

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152050
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000966
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
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251444
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.000123
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1461806
Hom.:
0
Cov.:
32
AF XY:
0.0000110
AC XY:
8
AN XY:
727220
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.0000224
AC:
1
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111970
Other (OTH)
AF:
0.0000994
AC:
6
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.518
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.0000329
AC:
5
AN:
152050
Hom.:
0
Cov.:
32
AF XY:
0.0000404
AC XY:
3
AN XY:
74240
show subpopulations
African (AFR)
AF:
0.0000966
AC:
4
AN:
41412
American (AMR)
AF:
0.00
AC:
0
AN:
15254
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10574
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
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:
0.0000386
Hom.:
0
Bravo
AF:
0.0000302
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis 1 Uncertain:2
Apr 17, 2024
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 196 of the PPT1 protein (p.Arg196Cys). This variant is present in population databases (rs376715840, gnomAD 0.01%). 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: 206649). 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%. 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. -

Dec 09, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Aug 01, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.586C>T (p.R196C) alteration is located in exon 6 (coding exon 6) of the PPT1 gene. This alteration results from a C to T substitution at nucleotide position 586, causing the arginine (R) at amino acid position 196 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Uncertain
0.13
D
BayesDel_noAF
Pathogenic
0.18
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.97
D;.;.;.;.;.;.
Eigen
Pathogenic
0.72
Eigen_PC
Pathogenic
0.70
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Pathogenic
0.98
.;D;D;D;D;D;D
M_CAP
Uncertain
0.24
D
MetaRNN
Pathogenic
0.92
D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.99
D
MutationAssessor
Pathogenic
2.9
M;.;.;.;.;.;.
PhyloP100
4.8
PrimateAI
Benign
0.47
T
PROVEAN
Pathogenic
-4.8
.;.;.;.;.;D;.
REVEL
Pathogenic
0.81
Sift
Uncertain
0.013
.;.;.;.;.;D;.
Sift4G
Uncertain
0.017
.;.;.;.;.;D;.
Polyphen
1.0
D;.;.;.;.;D;.
Vest4
0.68
MVP
0.98
MPC
0.61
ClinPred
0.98
D
GERP RS
5.8
Varity_R
0.52
gMVP
0.54
Mutation Taster
=36/64
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: rs376715840; hg19: chr1-40546110; COSMIC: COSV65655238; COSMIC: COSV65655238; API