rs200813294

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_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

Clinical Significance

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

Conservation

PhyloP100: 9.72

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 Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a chain Palmitoyl-protein thioesterase 1 (size 278) in uniprot entity PPT1_HUMAN there are 88 pathogenic changes around while only 6 benign (94%) in NM_000310.4

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.899

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
PPT1	NM_000310.4 linkuse as main transcript	c.802C>T	p.Arg268Cys	missense_variant	9/9	ENST00000642050.2
PPT1	NM_001363695.2 linkuse as main transcript	c.730C>T	p.Arg244Cys	missense_variant	8/8
PPT1	NM_001142604.2 linkuse as main transcript	c.493C>T	p.Arg165Cys	missense_variant	6/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PPT1	ENST00000642050.2 linkuse as main transcript	c.802C>T	p.Arg268Cys	missense_variant	9/9		NM_000310.4	P1	P50897-1

Frequencies

GnomAD3 genomes

AF:

0.0000723

AC:

AN:

152134

Hom.:

Cov.:

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

GnomAD3 exomes

AF:

0.0000796

AC:

AN:

251366

Hom.:

AF XY:

0.0000810

AC XY:

AN XY:

135850

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 SAS 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.:

Cov.:

AF XY:

0.000125

AC XY:

AN XY:

727210

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000447

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:

0.000154

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.0000854

AC:

AN:

152252

Hom.:

Cov.:

AF XY:

0.0000940

AC XY:

AN XY:

74460

show subpopulations

Gnomad4 AFR

AF:

0.0000482

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000132

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000582

Hom.:

Bravo

AF:

0.0000869

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.000123

AC:

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

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Oct 13, 2022	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. -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Oct 31, 2018	- -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 12, 2018

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

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 31, 2023

Has not been previously published as pathogenic or benign to our knowledge; 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: 25741868) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.18

BayesDel_addAF

Pathogenic

0.27

BayesDel_noAF

Pathogenic

0.43

Cadd

Pathogenic

Dann

Uncertain

1.0

DEOGEN2

Pathogenic

0.97

D;.;.;.;.;.;.

Eigen

Uncertain

0.55

Eigen_PC

Uncertain

0.46

FATHMM_MKL

Pathogenic

0.98

M_CAP

Pathogenic

0.35

MetaRNN

Pathogenic

0.90

D;D;D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.3

M;.;.;.;.;.;.

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Benign

0.47

Polyphen

1.0

D;.;.;.;.;D;.

Vest4

0.65, 0.58

MVP

0.97

MPC

0.23

ClinPred

0.87

GERP RS

4.9

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.76

gMVP

0.52

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