11-6615491-T-G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1PM2BP4

The NM_000391.4(TPP1):​c.1217A>C​(p.Tyr406Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. Y406C) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TPP1
NM_000391.4 missense

Scores

3
4
11

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

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
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.319669).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TPP1NM_000391.4 linkc.1217A>C p.Tyr406Ser 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>C p.Tyr406Ser missense_variant Exon 10 of 13 1 NM_000391.4 ENSP00000299427.6

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251462
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461882
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
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:
0.00
AC:
0
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:
8.99e-7
AC:
1
AN:
1112004
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Uncertain:1
May 20, 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 serine, which is neutral and polar, at codon 406 of the TPP1 protein (p.Tyr406Ser). This variant is present in population databases (rs780670020, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with TPP1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.095
BayesDel_addAF
Pathogenic
0.36
D
BayesDel_noAF
Pathogenic
0.28
CADD
Benign
21
DANN
Benign
0.93
DEOGEN2
Benign
0.39
T;.;.;.;.;.;.
Eigen
Benign
-0.11
Eigen_PC
Benign
0.064
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.85
T;.;T;.;T;.;T
M_CAP
Uncertain
0.16
D
MetaRNN
Benign
0.32
T;T;T;T;T;T;T
MetaSVM
Uncertain
-0.15
T
MutationAssessor
Benign
0.62
N;.;.;.;.;.;.
PhyloP100
4.3
PrimateAI
Uncertain
0.64
T
PROVEAN
Benign
-1.1
N;N;.;.;.;.;.
REVEL
Uncertain
0.54
Sift
Benign
0.53
T;T;.;.;.;.;.
Sift4G
Benign
0.40
T;T;.;.;.;.;.
Vest4
0.49
ClinPred
0.25
T
GERP RS
5.1
Varity_R
0.53
gMVP
0.89
Mutation Taster
=33/67
disease causing

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

Publications

Other links and lift over

dbSNP: rs780670020; hg19: chr11-6636722; API