1-40080483-C-T

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PM1PM2PM5PP3_ModeratePP5_Very_Strong

The NM_000310.4(PPT1):​c.541G>A​(p.Val181Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000576 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V181L) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000062 ( 0 hom. )

Consequence

PPT1
NM_000310.4 missense

Scores

9
8
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:12

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 16 ACMG points.

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-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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.899
PP5
Variant 1-40080483-C-T is Pathogenic according to our data. 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.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PPT1NM_000310.4 linkc.541G>A p.Val181Met missense_variant Exon 6 of 9 ENST00000642050.2 NP_000301.1 P50897-1
PPT1NM_001363695.2 linkc.541G>A p.Val181Met missense_variant Exon 6 of 8 NP_001350624.1
PPT1NM_001142604.2 linkc.232G>A p.Val78Met 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>A p.Val181Met missense_variant Exon 6 of 9 NM_000310.4 ENSP00000493153.1 P50897-1

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000875
AC:
22
AN:
251372
AF XY:
0.0000662
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000185
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000623
AC:
91
AN:
1461548
Hom.:
0
Cov.:
32
AF XY:
0.0000550
AC XY:
40
AN XY:
727112
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.0000224
AC:
1
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:
0.0000375
AC:
2
AN:
53372
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000774
AC:
86
AN:
1111762
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60376
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
Heterozygous variant carriers
0
6
12
17
23
29
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000132
AC:
2
AN:
151758
Hom.:
0
Cov.:
32
AF XY:
0.0000270
AC XY:
2
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:
0.0000294
AC:
2
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
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:
0.0000512
Hom.:
0
Bravo
AF:
0.0000302
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000165
AC:
20
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:12
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis 1 Pathogenic:9
Jun 03, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 07, 2021
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Apr 12, 2021
Centre for Inherited Metabolic Diseases, Karolinska University Hospital
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 04, 2016
Equipe Genetique des Anomalies du Developpement, Université de Bourgogne
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 10, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 11, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: PPT1 c.541G>A (p.Val181Met) results in a conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8.7e-05 in 277014 control chromosomes (gnomAD). This frequency is not significantly higher than expected for a pathogenic variant in PPT1 causing Neuronal Ceroid-Lipofuscinosis (Batten Disease) (8.7e-05 vs 0.00073), allowing no conclusion about variant significance. c.541G>A has been reported in the literature in multiple homozygous and compound heterozygous individuals affected with Neuronal Ceroid-Lipofuscinosis (Batten Disease, Das_1998, Santorelli_2013, Poyato_2012). These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein enzyme activity. The most pronounced variant effect results in <10% of normal activity (Das_1998, Poyato_2012). No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as pathogenic. -

Mar 14, 2022
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 23, 2024
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 methionine, which is neutral and non-polar, at codon 181 of the PPT1 protein (p.Val181Met). This variant is present in population databases (rs148412181, gnomAD 0.02%). This missense change has been observed in individuals with neuronal ceroid lipofucinosis (NCL) (PMID: 9664077, 10191107, 10649502, 15464427, 19302939, 22387303, 23374165, 30541466). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 188857). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt PPT1 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects PPT1 function (PMID: 9664077, 11440996, 28878621). 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: 19302939, 21499717). 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. -

Jun 27, 2014
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Inborn genetic diseases Pathogenic:1
Jul 19, 2019
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V181M pathogenic mutation (also known as c.541G>A), located in coding exon 6 of the PPT1 gene, results from a G to A substitution at nucleotide position 541. The valine at codon 181 is replaced by methionine, an amino acid with highly similar properties. This mutation has been identified in multiple individuals with neuronal ceroid lipofuscinosis, including in the homozygous state in 3 individuals from 2 families (Das AK et al. J. Clin. Invest., 1998 Jul;102:361-70; Waliany S et al. Hum. Mutat., 2000 Feb;15:206-7; Mole SE et al. Hum. Mutat., 1999;14:199-215; Teixeira C et al. J. Neurol., 2003 Jun;250:661-7; P&eacute;rez Poyato MS et al. Gene, 2012 May;499:297-302; Santorelli FM et al. Orphanet J Rare Dis, 2013 Feb;8:19; Sheth J et al. BMC Neurol, 2018 Dec;18:203). Analysis of this mutation in SF9 cells as well as patient derived lymphoblasts showed o detectable palmitoyl-protein thioesterase activity (Das AK et al. Hum. Mol. Genet., 2001 Jun;10:1431-9). Another study suggested abnormal processing of protein containing this mutation (Pezzini F et al. Front Mol Neurosci, 2017 Aug;10:266). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

not provided Pathogenic:1
Jun 22, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Published functional studies demonstrate that V181M results in almost complete loss of wild-type function (Das et al., 2001); Located in the palmitate-binding site and it is hypothesized that the V181M substitution alters the active site pocket (Ohno et al., 2010); 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: 15464427, 12796825, 12125808, 28878621, 11073228, 11589007, 21990111, 21499717, 24091420, 15965709, 10649502, 31589614, 30541466, 33726816, 23374165, 33849402, 22387303, 11440996, 19793631, 9664077) -

Retinitis pigmentosa Pathogenic:1
Apr 01, 2021
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:curation

The p.Val181Met variant in PPT1 was identified in an individual with Retinitis pigmentosa, via a collaborative study between the Broad Institute's Center for Mendelian Genomics and the Pierce lab (https://oculargenomics.meei.harvard.edu/labs/pierce-lab/lab-members/). Through a review of available evidence we were able to apply the following criteria: PM2, PP3, PM3, PS3, PP1-M, PM1. Based on this evidence we have classified this variant as Pathogenic. If you have any questions about the classification please reach out to the Pierce Lab. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.84
BayesDel_addAF
Pathogenic
0.38
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.98
D;.;.;.;.;.;.
Eigen
Uncertain
0.58
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.96
.;D;D;D;D;D;D
M_CAP
Uncertain
0.29
D
MetaRNN
Pathogenic
0.90
D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.8
H;.;.;.;.;.;.
PhyloP100
7.8
PrimateAI
Benign
0.43
T
PROVEAN
Uncertain
-2.5
.;.;.;.;.;N;.
REVEL
Pathogenic
0.89
Sift
Uncertain
0.0010
.;.;.;.;.;D;.
Sift4G
Uncertain
0.0020
.;.;.;.;.;D;.
Polyphen
1.0
D;.;.;.;.;D;.
Vest4
0.85
MVP
0.96
MPC
0.57
ClinPred
0.90
D
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.91
gMVP
0.60
Mutation Taster
=3/97
disease causing (ClinVar)

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