dbSNP rs771335558: TCTN2:p.Trp689Ser (chr12-123707685-G-C) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_024809.5(TCTN2):c.2066G>C(p.Trp689Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000682 in 1,614,010 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

TCTN2
NM_024809.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 6.69

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:

ENSG00000255839 (HGNC:):

ENSG00000255839 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TCTN2	NM_024809.5 link	c.2066G>C	p.Trp689Ser	missense_variant	Exon 18 of 18	ENST00000303372.7	NP_079085.2	Q96GX1-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TCTN2	ENST00000303372.7 link	c.2066G>C	p.Trp689Ser	missense_variant	Exon 18 of 18	1	NM_024809.5	ENSP00000304941.5		Q96GX1-1

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152136

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000161

AC:

AN:

249056

Hom.:

AF XY:

0.00000742

AC XY:

AN XY:

134822

show subpopulations

Gnomad AFR exome

AF:

0.000246

Gnomad AMR exome

AF:

0.00

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:

0.00000410

AC:

AN:

1461874

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.000149

Gnomad4 AMR exome

AF:

0.00

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:

0.0000166

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152136

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74320

show subpopulations

Gnomad4 AFR

AF:

0.000121

Gnomad4 AMR

AF:

0.00

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:

0.0000529

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

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

Uncertain:1

Jul 30, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tryptophan, which is neutral and slightly polar, with serine, which is neutral and polar, at codon 689 of the TCTN2 protein (p.Trp689Ser). This variant is present in population databases (rs771335558, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with TCTN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 461765). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -

Meckel syndrome, type 8;C4084841:Joubert syndrome 24

Uncertain:1

May 17, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.18

BayesDel_addAF

Uncertain

0.021

BayesDel_noAF

Uncertain

0.090

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.68

.;D

Eigen

Pathogenic

0.74

Eigen_PC

Pathogenic

0.73

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.66

T;T

M_CAP

Uncertain

0.11

MetaRNN

Uncertain

0.74

D;D

MetaSVM

Uncertain

0.40

MutationAssessor

Uncertain

2.6

.;M

PrimateAI

Benign

0.43

PROVEAN

Pathogenic

-6.1

D;D

REVEL

Pathogenic

0.65

Sift

Benign

0.19

T;T

Sift4G

Uncertain

0.0020

D;D

Polyphen

1.0

.;D

Vest4

0.58

MVP

0.98

MPC

0.70

ClinPred

0.88

GERP RS

5.7

Varity_R

0.53

gMVP

0.88

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