rs201010803

Positions:

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_024809.5(TCTN2):c.1751T>A(p.Ile584Lys) variant causes a missense change. The variant allele was found at a frequency of 0.00000434 in 1,613,630 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 30)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

TCTN2
NM_024809.5 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 5.96

Variant links:

Genes affected

TCTN2 (HGNC:25774): (tectonic family member 2) This gene encodes a type I membrane protein that belongs to the tectonic family. Studies in mice suggest that this protein may be involved in hedgehog signaling, and essential for ciliogenesis. Mutations in this gene are associated with Meckel syndrome type 8. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2011]

TCTN2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.954

PP5

Variant 12-123704670-T-A is Pathogenic according to our data. Variant chr12-123704670-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 217698.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr12-123704670-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TCTN2	NM_024809.5 link	c.1751T>A	p.Ile584Lys	missense_variant	15/18	ENST00000303372.7	NP_079085.2	Q96GX1-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TCTN2	ENST00000303372.7 link	c.1751T>A	p.Ile584Lys	missense_variant	15/18	1	NM_024809.5	ENSP00000304941.5		Q96GX1-1

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151644

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000132

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251484

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135916

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000145

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461868

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727238

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000112

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151762

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74156

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000132

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Meckel-Gruber syndrome;C0431399:Familial aplasia of the vermis

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 11, 2023

For these reasons, this variant has been classified as Pathogenic. 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 TCTN2 protein function. ClinVar contains an entry for this variant (Variation ID: 217698). This missense change has been observed in individual(s) with Joubert syndrome (PMID: 26092869). This variant is present in population databases (rs201010803, gnomAD 0.01%). This sequence change replaces isoleucine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 584 of the TCTN2 protein (p.Ile584Lys). -

Joubert syndrome and related disorders

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Aug 10, 2021

Variant summary: TCTN2 c.1751T>A (p.Ile584Lys) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251484 control chromosomes. c.1751T>A has been reported in the literature in three individuals affected with Joubert Syndrome, presumably from the same family (Bachmann-Gagescu_2015, Phelps_2018). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Familial aplasia of the vermis

Pathogenic:1

Pathogenic, criteria provided, single submitter

research

UW Hindbrain Malformation Research Program, University of Washington

Feb 23, 2015

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.97

BayesDel_addAF

Pathogenic

0.25

BayesDel_noAF

Pathogenic

0.37

CADD

Pathogenic

DANN

Benign

0.95

DEOGEN2

Uncertain

0.78

.;D

Eigen

Pathogenic

0.69

Eigen_PC

Uncertain

0.62

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Benign

0.80

T;T

M_CAP

Pathogenic

0.40

MetaRNN

Pathogenic

0.95

D;D

MetaSVM

Pathogenic

0.81

MutationAssessor

Pathogenic

3.1

.;M

PrimateAI

Uncertain

0.54

PROVEAN

Pathogenic

-5.8

D;D

REVEL

Pathogenic

0.90

Sift

Uncertain

0.0010

D;D

Sift4G

Pathogenic

0.0

D;D

Polyphen

1.0

.;D

Vest4

0.91

MVP

0.98

MPC

0.84

ClinPred

0.94

GERP RS

5.6

Varity_R

0.78

gMVP

0.98

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over