1-40097125-C-G

Variant names:

• chr1-40097125-C-G
• NM_000310.4:c.114G>C
• PPT1 p.Trp38Cys

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PS1_Moderate PM1 PM2 PP3_Strong

The NM_000310.4(PPT1):​c.114G>C​(p.Trp38Cys) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W38S) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PPT1 NM_000310.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.48
• 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: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp, G2P, ClinGen, Myriad Women's Health

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PS1: Transcript NM_000310.4 (PPT1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000310.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98

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.114G>C	p.Trp38Cys	missense	Exon 1 of 9	NP_000301.1	P50897-1
	PPT1	NM_001363695.2		c.114G>C	p.Trp38Cys	missense	Exon 1 of 8	NP_001350624.1	Q5T0S4
	PPT1	NM_001142604.2		c.114G>C	p.Trp38Cys	missense	Exon 1 of 6	NP_001136076.1	P50897-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PPT1	ENST00000642050.2	MANE Select	c.114G>C	p.Trp38Cys	missense	Exon 1 of 9	ENSP00000493153.1	P50897-1
	PPT1	ENST00000433473.8	TSL:1	c.114G>C	p.Trp38Cys	missense	Exon 1 of 9	ENSP00000394863.4	A0A2C9F2P4
	PPT1	ENST00000530704.6	TSL:1	n.114G>C		non_coding_transcript_exon	Exon 1 of 9	ENSP00000431655.1	E9PK48

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.99	D
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.92	D
M_CAP	Pathogenic	0.60	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.8	H
PhyloP100		6.5
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-12	D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
PromoterAI		-0.00090	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.97
Mutation Taster		=2/98	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		Details are displayed if max score is > 0.2

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr1-40562797;