12-110640385-C-G

Variant names:

• chr12-110640385-C-G
• rs368536784
• NM_001082538.3:c.846C>G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_001082538.3(TCTN1):​c.846C>G​(p.Val282Val) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,168 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: TCTN1 NM_001082538.3 splice_region, synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.344
• Publications: 0 publications found

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]

HVCN1 (HGNC:28240): (hydrogen voltage gated channel 1) This gene encodes a voltage-gated protein channel protein expressed more highly in certain cells of the immune system. Phagocytic cells produce superoxide anions which require this channel protein, and in B cells this same process facilitates antibody production. This same channel protein, however, can also regulate functions in other cells including spermatozoa. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2012]

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.6).
• BP6: Variant 12-110640385-C-G is Benign according to our data. Variant chr12-110640385-C-G is described in ClinVar as Likely_benign. ClinVar VariationId is 238283.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.344 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001082538.3. 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
	TCTN1	NM_001082538.3	MANE Select	c.846C>G	p.Val282Val	splice_region synonymous	Exon 8 of 15	NP_001076007.1
	TCTN1	NM_001082537.3		c.846C>G	p.Val282Val	splice_region synonymous	Exon 8 of 15	NP_001076006.1
	TCTN1	NM_024549.6		c.804C>G	p.Val268Val	splice_region synonymous	Exon 8 of 15	NP_078825.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TCTN1	ENST00000397659.9	TSL:1 MANE Select	c.846C>G	p.Val282Val	splice_region synonymous	Exon 8 of 15	ENSP00000380779.4
	TCTN1	ENST00000551590.5	TSL:1	c.846C>G	p.Val282Val	splice_region synonymous	Exon 8 of 15	ENSP00000448735.1
	TCTN1	ENST00000397655.7	TSL:1	c.804C>G	p.Val268Val	splice_region synonymous	Exon 8 of 15	ENSP00000380775.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152168 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249528 AF XY: 0.00

Gnomad AFR exome AF: 0.0000646

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152168 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74324

African (AFR) AF: 0.0000241 AC: 1 AN: 41434

American (AMR) AF: 0.00 AC: 0 AN: 15274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5204

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68036

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000113

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Meckel-Gruber syndrome;C0431399:Joubert syndrome Benign:1

Feb 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.60
CADD	Benign	6.7
DANN	Benign	0.69
PhyloP100		0.34

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

Other links and lift over

dbSNP: rs368536784; hg19: chr12-111078190;