rs386833637

Variant names:

• chr1-40092149-CAAG-C
• rs386833637
• NM_000310.4:c.255_257delCTT

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PS3 PM1 PM2 PM4_Supporting PP5_Very_Strong

The NM_000310.4(PPT1):​c.255_257delCTT​(p.Phe85del) variant causes a disruptive inframe deletion change. The variant allele was found at a frequency of 0.0000112 in 1,613,990 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000946441: Experimental studies have shown that this variant affects PPT1 function (PMID:11520175, 17565660)." and additional evidence is available in ClinVar. Synonymous variant affecting the same amino acid position (i.e. F85F) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: PPT1 NM_000310.4 disruptive_inframe_deletion
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 4.02
• Publications: 1 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: G2P, Myriad Women’s Health, Genomics England PanelApp, Orphanet, ClinGen, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 17 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV000946441: Experimental studies have shown that this variant affects PPT1 function (PMID: 11520175, 17565660).; SCV002103449: The most pronounced variant effect results in <10% of normal activity (Salonen_2001).
• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 12 uncertain in NM_000310.4
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_000310.4. Strenght limited to Supporting due to length of the change: 1aa.
• PP5: Variant 1-40092149-CAAG-C is Pathogenic according to our data. Variant chr1-40092149-CAAG-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 56185.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000310.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PPT1	NM_000310.4	MANE Select	c.255_257delCTT	p.Phe85del	disruptive_inframe_deletion	Exon 3 of 9	NP_000301.1	P50897-1
	PPT1	NM_001363695.2		c.255_257delCTT	p.Phe85del	disruptive_inframe_deletion	Exon 3 of 8	NP_001350624.1	Q5T0S4
	PPT1	NM_001142604.2		c.125-2640_125-2638delCTT		intron	N/A	NP_001136076.1	P50897-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PPT1	ENST00000642050.2	MANE Select	c.255_257delCTT	p.Phe85del	disruptive_inframe_deletion	Exon 3 of 9	ENSP00000493153.1	P50897-1
	PPT1	ENST00000433473.8	TSL:1	c.252_254delCTT	p.Phe84del	disruptive_inframe_deletion	Exon 3 of 9	ENSP00000394863.4	A0A2C9F2P4
	PPT1	ENST00000530704.6	TSL:1	n.255_257delCTT		non_coding_transcript_exon	Exon 3 of 9	ENSP00000431655.1	E9PK48

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152166 Hom.: 0 Cov.: 33

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

GnomAD4 exome AF: 0.0000109 AC: 16 AN: 1461824 Hom.: 0 AF XY: 0.0000110 AC XY: 8 AN XY: 727226

African (AFR) AF: 0.00 AC: 0 AN: 33480

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

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: 0.0000144 AC: 16 AN: 1111960

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152166 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74322

African (AFR) AF: 0.00 AC: 0 AN: 41438

American (AMR) AF: 0.00 AC: 0 AN: 15270

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000113

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
5	-	-	Neuronal ceroid lipofuscinosis 1 (5)
1	-	-	Neuronal ceroid lipofuscinosis (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		4.0
Mutation Taster		=11/89	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs386833637; hg19: chr1-40557821;