rs780670020

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1PP3

The NM_000391.4(TPP1):​c.1217A>G​(p.Tyr406Cys) variant causes a missense change. The variant allele was found at a frequency of 0.000102 in 1,614,040 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. Y406S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

TPP1
NM_000391.4 missense

Scores

7
9
3

Clinical Significance

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

Conservation

PhyloP100: 4.28

Publications

1 publications found
Variant links:
Genes affected
TPP1 (HGNC:2073): (tripeptidyl peptidase 1) This gene encodes a member of the sedolisin family of serine proteases. The protease functions in the lysosome to cleave N-terminal tripeptides from substrates, and has weaker endopeptidase activity. It is synthesized as a catalytically-inactive enzyme which is activated and auto-proteolyzed upon acidification. Mutations in this gene result in late-infantile neuronal ceroid lipofuscinosis, which is associated with the failure to degrade specific neuropeptides and a subunit of ATP synthase in the lysosome. [provided by RefSeq, Jul 2008]
TPP1 Gene-Disease associations (from GenCC):
  • neuronal ceroid lipofuscinosis
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • neuronal ceroid lipofuscinosis 2
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Myriad Women’s Health, G2P, Orphanet
  • autosomal recessive spinocerebellar ataxia 7
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000391.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.791

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TPP1NM_000391.4 linkc.1217A>G p.Tyr406Cys missense_variant Exon 10 of 13 ENST00000299427.12 NP_000382.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TPP1ENST00000299427.12 linkc.1217A>G p.Tyr406Cys missense_variant Exon 10 of 13 1 NM_000391.4 ENSP00000299427.6

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152158
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000477
AC:
12
AN:
251462
AF XY:
0.0000441
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000173
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000110
AC:
161
AN:
1461882
Hom.:
0
Cov.:
34
AF XY:
0.000102
AC XY:
74
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000134
AC:
6
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000138
AC:
153
AN:
1112004
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
13
26
39
52
65
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152158
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41424
American (AMR)
AF:
0.0000654
AC:
1
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000675
Hom.:
0
Bravo
AF:
0.0000378
TwinsUK
AF:
0.000539
AC:
2
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.0000412
AC:
5
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Sep 11, 2018
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A variant of uncertain significance has been identified in the TPP1 gene. The Y406C variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The Y406C variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species, and in silico analysis predicts this variant is probably damaging to the protein structure/function. Based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Jul 05, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 406 of the TPP1 protein (p.Tyr406Cys). This variant is present in population databases (rs780670020, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with TPP1-related conditions. ClinVar contains an entry for this variant (Variation ID: 207589). 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 TPP1 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. -

Neuronal ceroid lipofuscinosis 2 Uncertain:1
Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.42
BayesDel_addAF
Pathogenic
0.26
D
BayesDel_noAF
Pathogenic
0.40
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.75
D;.;.;.;.;.;.
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.95
D;.;D;.;D;.;D
M_CAP
Pathogenic
0.29
D
MetaRNN
Pathogenic
0.79
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.71
D
MutationAssessor
Pathogenic
3.4
M;.;.;.;.;.;.
PhyloP100
4.3
PrimateAI
Uncertain
0.70
T
PROVEAN
Uncertain
-3.1
D;D;.;.;.;.;.
REVEL
Pathogenic
0.81
Sift
Benign
0.14
T;T;.;.;.;.;.
Sift4G
Benign
0.15
T;T;.;.;.;.;.
Polyphen
1.0
D;.;.;.;.;.;.
Vest4
0.85
MutPred
0.52
Loss of phosphorylation at Y406 (P = 0.0335);.;.;.;.;.;.;
MVP
0.99
MPC
0.82
ClinPred
0.83
D
GERP RS
5.1
Varity_R
0.68
gMVP
0.90
Mutation Taster
=41/59
disease causing

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

Other links and lift over

dbSNP: rs780670020; hg19: chr11-6636722; API