10-95664120-T-A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_015631.6(TCTN3):​c.1771A>T​(p.Ile591Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,613,998 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict 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. I591T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

TCTN3
NM_015631.6 missense

Scores

3
16

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -2.94

Publications

0 publications found
Variant links:
Genes affected
TCTN3 (HGNC:24519): (tectonic family member 3) This gene encodes a member of the tectonic gene family which functions in Hedgehog signal transduction and development of the neural tube. Mutations in this gene have been associated with Orofaciodigital Syndrome IV and Joubert Syndrom 18. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Sep 2012]
TCTN3 Gene-Disease associations (from GenCC):
  • ciliopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • orofaciodigital syndrome IV
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet, Laboratory for Molecular Medicine
  • Joubert syndrome 18
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • Meckel syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • orofaciodigital syndrome type 6
    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 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.082145154).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TCTN3NM_015631.6 linkc.1771A>T p.Ile591Phe missense_variant Exon 14 of 14 ENST00000371217.10 NP_056446.4 Q6NUS6-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TCTN3ENST00000371217.10 linkc.1771A>T p.Ile591Phe missense_variant Exon 14 of 14 1 NM_015631.6 ENSP00000360261.5 Q6NUS6-1
TCTN3ENST00000265993.13 linkc.1825A>T p.Ile609Phe missense_variant Exon 14 of 14 1 ENSP00000265993.9 A0A0C4DFN5
TCTN3ENST00000430368.6 linkc.1327A>T p.Ile443Phe missense_variant Exon 10 of 10 2 ENSP00000387567.1 Q6NUS6-5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
33
show subpopulations
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251476
AF XY:
0.0000147
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:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000212
AC:
31
AN:
1461890
Hom.:
0
Cov.:
31
AF XY:
0.0000261
AC XY:
19
AN XY:
727246
show subpopulations
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:
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:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000270
AC:
30
AN:
1112008
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
2
4
5
7
9
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74296
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41414
American (AMR)
AF:
0.00
AC:
0
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10594
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
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:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000165
AC:
2

ClinVar

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

Submissions by phenotype

Orofacial-digital syndrome IV;C3553758:Joubert syndrome 18 Uncertain:1
Oct 13, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine with phenylalanine at codon 591 of the TCTN3 protein (p.Ile591Phe). The isoleucine residue is weakly conserved and there is a small physicochemical difference between isoleucine and phenylalanine. This variant is present in population databases (rs746968875, ExAC 0.003%). This variant has not been reported in the literature in individuals affected with TCTN3-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
0.071
BayesDel_addAF
Benign
-0.20
T
BayesDel_noAF
Benign
-0.50
CADD
Benign
0.026
DANN
Benign
0.65
DEOGEN2
Benign
0.0080
T;T;.;.
Eigen
Benign
-2.1
Eigen_PC
Benign
-2.2
FATHMM_MKL
Benign
0.053
N
LIST_S2
Benign
0.49
T;.;T;T
M_CAP
Benign
0.048
D
MetaRNN
Benign
0.082
T;T;T;T
MetaSVM
Benign
-0.80
T
MutationAssessor
Benign
1.5
L;L;.;.
PhyloP100
-2.9
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.30
.;.;.;N
REVEL
Uncertain
0.30
Sift
Uncertain
0.0090
.;.;.;D
Sift4G
Uncertain
0.056
T;T;T;T
Polyphen
0.12
B;B;.;.
Vest4
0.17
MVP
0.18
MPC
0.26
ClinPred
0.082
T
GERP RS
-12
Varity_R
0.027
gMVP
0.53
Mutation Taster
=88/12
polymorphism

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: rs746968875; hg19: chr10-97423877; API