12-123688184-G-T

Variant names:

• chr12-123688184-G-T
• rs7313032
• NM_024809.5:c.891+7G>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_024809.5(TCTN2):​c.891+7G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 30)
• Consequence: TCTN2 NM_024809.5 splice_region, intron
• Scores: Splicing: ADA: 0.0002274
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.407
• Publications: 20 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, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• Joubert syndrome

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TCTN2	NM_024809.5	MANE Select	c.891+7G>T		splice_region intron	N/A	NP_079085.2
	TCTN2	NM_001143850.3		c.888+7G>T		splice_region intron	N/A	NP_001137322.1
	TCTN2	NM_001410989.1		c.891+7G>T		splice_region intron	N/A	NP_001397918.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TCTN2	ENST00000303372.7	TSL:1 MANE Select	c.891+7G>T		splice_region intron	N/A	ENSP00000304941.5
	TCTN2	ENST00000426174.6	TSL:2	c.888+7G>T		splice_region intron	N/A	ENSP00000395171.2
	TCTN2	ENST00000679504.1		c.888+7G>T		splice_region intron	N/A	ENSP00000505006.1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Cov.: 37

GnomAD4 genome Cov.: 30

Alfa AF: 0.00 Hom.: 7019

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	0.11
DANN	Benign	0.71
PhyloP100		-0.41

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00023
dbscSNV1_RF	Benign	0.0
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: rs7313032; hg19: chr12-124172731;