rs863225222

Variant names:

• chr12-123671310-TG-T
• rs863225222
• NM_024809.5:c.76delG

Your query was ambiguous. Multiple possible variants found:

• chr12-123671310-TG-T
• chr12-123671310-TG-TGG
• chr12-123671310-TG-TGGG
• chr12-123671310-TG-TGGGGG

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_024809.5(TCTN2):​c.76delG​(p.Asp26ThrfsTer27) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,613,452 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: TCTN2 NM_024809.5 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 0.591
• Publications: 4 publications found

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 Gene-Disease associations (from GenCC):

• Joubert syndrome 24

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), PanelApp Australia, G2P, Ambry Genetics
• Meckel syndrome, type 8

  Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia
• Joubert syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Meckel syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 54 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-123671310-TG-T is Pathogenic according to our data. Variant chr12-123671310-TG-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 217701.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024809.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TCTN2	NM_024809.5	MANE Select	c.76delG	p.Asp26ThrfsTer27	frameshift	Exon 1 of 18	NP_079085.2
	TCTN2	NM_001143850.3		c.76delG	p.Asp26ThrfsTer27	frameshift	Exon 1 of 18	NP_001137322.1	Q96GX1-2
	TCTN2	NM_001410989.1		c.76delG	p.Asp26ThrfsTer27	frameshift	Exon 1 of 17	NP_001397918.1	A0A7P0T8X4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TCTN2	ENST00000303372.7	TSL:1 MANE Select	c.76delG	p.Asp26ThrfsTer27	frameshift	Exon 1 of 18	ENSP00000304941.5	Q96GX1-1
	TCTN2	ENST00000426174.6	TSL:2	c.76delG	p.Asp26ThrfsTer27	frameshift	Exon 1 of 18	ENSP00000395171.2	Q96GX1-2
	TCTN2	ENST00000965363.1		c.76delG	p.Asp26ThrfsTer27	frameshift	Exon 1 of 17	ENSP00000635422.1

Frequencies

GnomAD3 genomes AF: 0.00000659 AC: 1 AN: 151860 Hom.: 0 Cov.: 32

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: 0.00000803 AC: 2 AN: 248992 AF XY: 0.0000148

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: 0.0000178

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000889 AC: 13 AN: 1461592 Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8 AN XY: 727092

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44702

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53224

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000117 AC: 13 AN: 1111958

Other (OTH) AF: 0.00 AC: 0 AN: 60388

GnomAD4 genome AF: 0.00000659 AC: 1 AN: 151860 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74178

African (AFR) AF: 0.00 AC: 0 AN: 41324

American (AMR) AF: 0.00 AC: 0 AN: 15238

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5172

South Asian (SAS) AF: 0.00 AC: 0 AN: 4812

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10578

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67956

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	-	-	Joubert syndrome (1)
1	-	-	Meckel syndrome, type 8;C4084841:Joubert syndrome 24 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.59
Mutation Taster		=10/190	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs863225222; hg19: chr12-124155857; COSMIC: COSV107324523;