chr12-123695276-G-T

Position:

• chr12-123695276-G-T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1 PM2 PP3_Moderate PP5_Moderate

The NM_024809.5(TCTN2):​c.1291G>T​(p.Glu431Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TCTN2 NM_024809.5 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: -1.22

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]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 12-123695276-G-T is Pathogenic according to our data. Variant chr12-123695276-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 217699.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr12-123695276-G-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TCTN2	NM_024809.5	c.1291G>T	p.Glu431Ter	stop_gained	11/18	ENST00000303372.7	NP_079085.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TCTN2	ENST00000303372.7	c.1291G>T	p.Glu431Ter	stop_gained	11/18	1	NM_024809.5	ENSP00000304941	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial aplasia of the vermis Pathogenic:1

Pathogenic, criteria provided, single submitter

research

UW Hindbrain Malformation Research Program, University of Washington

Feb 23, 2015

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Uncertain	0.13
CADD	Pathogenic	34
DANN	Benign	0.96
Eigen	Benign	-0.41
Eigen_PC	Benign	-0.80
FATHMM_MKL	Benign	0.025	N
MutationTaster	Benign	1.0	A;A
Vest4		0.23
GERP RS		-7.6

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.85		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.85		Position offset: 21

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs863225221; hg19: chr12-124179823;