chr1-40092082-A-C

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000310.4(PPT1):c.325T>G(p.Tyr109Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000576 in 1,614,014 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. Y109C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000063 ( 0 hom. )

Consequence

PPT1
NM_000310.4 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 9.10

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 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 chr1-40092081-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1969122.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.988

PP5

Variant 1-40092082-A-C is Pathogenic according to our data. Variant chr1-40092082-A-C is described in ClinVar as [Pathogenic]. Clinvar id is 56190.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-40092082-A-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PPT1	NM_000310.4 link	c.325T>G	p.Tyr109Asp	missense_variant	Exon 3 of 9	ENST00000642050.2	NP_000301.1	P50897-1
PPT1	NM_001363695.2 link	c.325T>G	p.Tyr109Asp	missense_variant	Exon 3 of 8		NP_001350624.1
PPT1	NM_001142604.2 link	c.125-2570T>G		intron_variant	Intron 1 of 5		NP_001136076.1	P50897-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PPT1	ENST00000642050.2 link	c.325T>G	p.Tyr109Asp	missense_variant	Exon 3 of 9		NM_000310.4	ENSP00000493153.1		P50897-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152220

Hom.:

Cov.:

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

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251450

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135890

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000629

AC:

AN:

1461794

Hom.:

Cov.:

AF XY:

0.0000770

AC XY:

AN XY:

727202

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000818

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152220

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74364

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000307

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis 1

Pathogenic:4

Jan 10, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Juha Muilu Group; Institute for Molecular Medicine Finland (FIMM)

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

May 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with aspartic acid, which is acidic and polar, at codon 109 of the PPT1 protein (p.Tyr109Asp). This variant is present in population databases (rs386833642, gnomAD 0.0009%). This missense change has been observed in individual(s) with neuronal ceroid lipofuscinosis (PMID: 9664077, 10191107, 21990111). ClinVar contains an entry for this variant (Variation ID: 56190). 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 95%. Experimental studies have shown that this missense change affects PPT1 function (PMID: 11440996). For these reasons, this variant has been classified as Pathogenic. -

May 25, 2020

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.1.1, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss-of-function is a known mechanism of disease for this gene. (N) 0106 - This gene is known to be associated with autosomal recessive disease. (N) 0200 - Variant is predicted to result in a missense amino acid change from tyrosine to aspartic acid (exon 3). (N) 0251 - Variant is heterozygous. (N) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (1 Heterozygote, 0 Homozygotes). (P) 0501 - Missense variant consistently predicted to be damaging by multiple in-silico tools or highly conserved with a major amino acid change. (P) 0600 - Variant is located in an annotated domain or motif (palmitoyl protein thioesterase domain, PDB). (N) 0705 - No comparable variants have previous evidence for pathogenicity. (N) 0801 - Strong previous evidence of pathogenicity in unrelated individuals (ClinVar, Das, AK. et al. (1998), Hofmann, SL. et al. (1999), Das, AK. et al. (2001), Kousi, M. et al. (2012), Teixeira, C. et al. (2013)). (P) 0905 - No segregation evidence has been identified for this variant. (N) 1001 - Strong functional evidence supporting abnormal protein function (Das, AK. et al. (2001)). (P) 1208 - Inheritance information for this variant is not currently available. (N) -

not provided

Pathogenic:1

Feb 11, 2022

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Published functional studies demonstrate a damaging effect with significantly impaired enzyme activity (Das et al., 2001); 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: 17565660, 10191107, 21990111, 11440996, 9664077, 11073228, 15719035) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.98

BayesDel_addAF

Pathogenic

0.58

BayesDel_noAF

Pathogenic

0.60

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.98

D;.;.;.;.

Eigen

Pathogenic

0.97

Eigen_PC

Pathogenic

0.90

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.92

.;D;D;D;D

M_CAP

Pathogenic

0.38

MetaRNN

Pathogenic

0.99

D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.6

H;.;.;.;.

PrimateAI

Uncertain

0.69

REVEL

Pathogenic

0.98

Polyphen

1.0

D;.;.;.;.

MutPred

0.95

Gain of disorder (P = 0.0057);.;.;Gain of disorder (P = 0.0057);Gain of disorder (P = 0.0057);

MVP

0.96

MPC

0.78

ClinPred

1.0

GERP RS

5.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.99

gMVP

0.95

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over