chr12-123706833-T-C

Position:

• chr12-123706833-T-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The ENST00000303372.7(TCTN2):​c.1877T>C​(p.Leu626Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,892 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L626L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: TCTN2 ENST00000303372.7 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.354

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 Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.05162725).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TCTN2	NM_024809.5	c.1877T>C	p.Leu626Ser	missense_variant	16/18	ENST00000303372.7	NP_079085.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TCTN2	ENST00000303372.7	c.1877T>C	p.Leu626Ser	missense_variant	16/18	1	NM_024809.5	ENSP00000304941	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251494 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135922

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461892 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727246

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.042	T
BayesDel_noAF	Benign	-0.30
CADD	Benign	14
DANN	Benign	0.67
DEOGEN2	Benign	0.15	.;T
Eigen	Benign	-0.91
Eigen_PC	Benign	-0.90
FATHMM_MKL	Benign	0.021	N
LIST_S2	Benign	0.73	T;T
M_CAP	Benign	0.042	D
MetaRNN	Benign	0.052	T;T
MetaSVM	Benign	-0.83	T
MutationAssessor	Uncertain	2.5	.;M
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.90	N;N
REVEL	Benign	0.11
Sift	Benign	0.89	T;T
Sift4G	Benign	0.49	T;T
Polyphen		0.040	.;B
Vest4		0.34
MutPred		0.38		.;Gain of catalytic residue at L630 (P = 8e-04);
MVP		0.46
MPC		0.22
ClinPred		0.98	D
GERP RS		2.5
Varity_R		0.054
gMVP		0.59

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

Publications

LitVar

Other links and lift over

dbSNP: rs786204788; hg19: chr12-124191380;