rs386833634

Variant names:

• chr1-40092462-AT-A
• rs386833634
• NM_000310.4:c.169delA

Your query was ambiguous. Multiple possible variants found:

• chr1-40092462-AT-A
• chr1-40092462-AT-ATT

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000310.4(PPT1):​c.169delA​(p.Met57TrpfsTer14) variant causes a frameshift change. The variant allele was found at a frequency of 0.000000684 in 1,461,622 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PPT1 NM_000310.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 3.91
• Publications: 0 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-40092462-AT-A is Pathogenic according to our data. Variant chr1-40092462-AT-A is described in ClinVar as [Pathogenic]. Clinvar id is 2752503.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PPT1	NM_000310.4	c.169delA	p.Met57TrpfsTer14	frameshift_variant	Exon 2 of 9	ENST00000642050.2	NP_000301.1
PPT1	NM_001363695.2	c.169delA	p.Met57TrpfsTer14	frameshift_variant	Exon 2 of 8		NP_001350624.1
PPT1	NM_001142604.2	c.125-2951delA		intron_variant	Intron 1 of 5		NP_001136076.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PPT1	ENST00000642050.2	c.169delA	p.Met57TrpfsTer14	frameshift_variant	Exon 2 of 9		NM_000310.4	ENSP00000493153.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461622 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727126

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111776

Other (OTH) AF: 0.0000166 AC: 1 AN: 60386

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronal ceroid lipofuscinosis 1 Pathogenic:1

Jun 09, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (gnomAD no frequency). For these reasons, this variant has been classified as Pathogenic. This variant has not been reported in the literature in individuals affected with PPT1-related conditions. This sequence change creates a premature translational stop signal (p.Met57Trpfs*14) in the PPT1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in PPT1 are known to be pathogenic (PMID: 10679943, 21990111). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		3.9

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs386833634; hg19: chr1-40558134; COSMIC: COSV65655463; COSMIC: COSV65655463;