rs939858453

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The NM_000310.4(PPT1):c.587G>A(p.Arg196His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,728 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. R196C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

PPT1
NM_000310.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 2.58

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, 0.87

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
PPT1	NM_000310.4 linkuse as main transcript	c.587G>A	p.Arg196His	missense_variant	6/9	ENST00000642050.2
PPT1	NM_001363695.2 linkuse as main transcript	c.587G>A	p.Arg196His	missense_variant	6/8
PPT1	NM_001142604.2 linkuse as main transcript	c.278G>A	p.Arg93His	missense_variant	3/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PPT1	ENST00000642050.2 linkuse as main transcript	c.587G>A	p.Arg196His	missense_variant	6/9		NM_000310.4	P1	P50897-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

151934

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000726

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000656

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251448

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135896

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS 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:

0.00000479

AC:

AN:

1461794

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727200

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:

0.00000630

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

151934

Hom.:

Cov.:

AF XY:

0.0000539

AC XY:

AN XY:

74162

show subpopulations

Gnomad4 AFR

AF:

0.0000726

Gnomad4 AMR

AF:

0.0000656

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000329

Hom.:

Bravo

AF:

0.0000113

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

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Dec 14, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 28, 2021	This sequence change replaces arginine with histidine at codon 196 of the PPT1 protein (p.Arg196His). The arginine residue is moderately conserved and there is a small physicochemical difference between arginine and histidine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with PPT1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 10, 2022

The c.587G>A (p.R196H) alteration is located in exon 6 (coding exon 6) of the PPT1 gene. This alteration results from a G to A substitution at nucleotide position 587, causing the arginine (R) at amino acid position 196 to be replaced by a histidine (H). 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

0.12

BayesDel_addAF

Uncertain

0.11

BayesDel_noAF

Uncertain

0.090

Cadd

Uncertain

Dann

Uncertain

1.0

DEOGEN2

Pathogenic

0.95

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

Eigen

Benign

0.0039

Eigen_PC

Benign

0.080

FATHMM_MKL

Uncertain

0.88

M_CAP

Pathogenic

0.43

MetaRNN

Pathogenic

0.87

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

MetaSVM

Pathogenic

0.87

MutationAssessor

Uncertain

2.6

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

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Benign

0.41

Polyphen

0.37

B;.;.;.;.;B;.

Vest4

0.60

MutPred

0.78

Loss of catalytic residue at R196 (P = 0.0121);.;.;Loss of catalytic residue at R196 (P = 0.0121);Loss of catalytic residue at R196 (P = 0.0121);.;.;

MVP

0.98

MPC

0.48

ClinPred

0.94

GERP RS

4.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.51

gMVP

0.44

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