12-110614207-C-CTCCT

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_001082538.3(TCTN1):c.26_29dup(p.Val11ProfsTer72) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000982 in 1,425,812 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000098 (0 hom.)
• Consequence: TCTN1 NM_001082538.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 1.12

Genes affected

TCTN1 (HGNC:26113): (tectonic family member 1) This gene encodes a member of a family of secreted and transmembrane proteins. The orthologous gene in mouse functions downstream of smoothened and rab23 to modulate hedgehog signal transduction. This protein is a component of the tectonic-like complex, which forms a barrier between the ciliary axoneme and the basal body. A mutation in this gene was found in a family with Joubert syndrome-13. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2016]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 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 14 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-110614207-C-CTCCT is Pathogenic according to our data. Variant chr12-110614207-C-CTCCT is described in ClinVar as [Pathogenic]. Clinvar id is 1033279.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TCTN1	NM_001082538.3	c.26_29dup	p.Val11ProfsTer72	frameshift_variant	1/15	ENST00000397659.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TCTN1	ENST00000397659.9	c.26_29dup	p.Val11ProfsTer72	frameshift_variant	1/15	1	NM_001082538.3	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000534 AC: 1 AN: 187210 Hom.: 0 AF XY: 0.00000978 AC XY: 1 AN XY: 102278

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 SAS exome AF: 0.0000394

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000982 AC: 14 AN: 1425812 Hom.: 0 Cov.: 31 AF XY: 0.0000170 AC XY: 12 AN XY: 706030

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000147

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000339

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Joubert syndrome 13 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Feb 01, 2018

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1275375836; hg19: chr12-111052012;