6-32084566-CTT-C

Position:

chr6-32084566-CTT-C

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_001365276.2(TNXB):c.3290_3291del(p.Lys1097ArgfsTer48) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000168 in 1,608,920 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

TNXB
NM_001365276.2 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 1.13

Variant links:

Genes affected

TNXB (HGNC:11976): (tenascin XB) This gene encodes a member of the tenascin family of extracellular matrix glycoproteins. The tenascins have anti-adhesive effects, as opposed to fibronectin which is adhesive. This protein is thought to function in matrix maturation during wound healing, and its deficiency has been associated with the connective tissue disorder Ehlers-Danlos syndrome. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. It is one of four genes in this cluster which have been duplicated. The duplicated copy of this gene is incomplete and is a pseudogene which is transcribed but does not encode a protein. The structure of this gene is unusual in that it overlaps the CREBL1 and CYP21A2 genes at its 5' and 3' ends, respectively. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

TNXB links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PP5

Variant 6-32084566-CTT-C is Pathogenic according to our data. Variant chr6-32084566-CTT-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 8550.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr6-32084566-CTT-C is described in Lovd as [Pathogenic]. Variant chr6-32084566-CTT-C is described in Lovd as [Pathogenic]. Variant chr6-32084566-CTT-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TNXB	NM_001365276.2 linkuse as main transcript	c.3290_3291del	p.Lys1097ArgfsTer48	frameshift_variant	8/44	ENST00000644971.2	NP_001352205.1
TNXB	NM_019105.8 linkuse as main transcript	c.3290_3291del	p.Lys1097ArgfsTer48	frameshift_variant	8/44		NP_061978.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TNXB	ENST00000644971.2 linkuse as main transcript	c.3290_3291del	p.Lys1097ArgfsTer48	frameshift_variant	8/44		NM_001365276.2	ENSP00000496448		P22105-3
TNXB	ENST00000375244.7 linkuse as main transcript	c.3290_3291del	p.Lys1097ArgfsTer48	frameshift_variant	8/44	5		ENSP00000364393		P22105-3
TNXB	ENST00000647633.1 linkuse as main transcript	c.4031_4032del	p.Lys1344ArgfsTer48	frameshift_variant	9/45			ENSP00000497649	P1

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152194

Hom.:

Cov.:

show subpopulations

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:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000246

AC:

AN:

244136

Hom.:

AF XY:

0.0000150

AC XY:

AN XY:

133606

show subpopulations

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:

0.0000455

Gnomad OTH exome

AF:

0.000167

GnomAD4 exome

AF:

0.0000151

AC:

AN:

1456726

Hom.:

AF XY:

0.0000152

AC XY:

AN XY:

724488

show subpopulations

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:

0.0000198

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152194

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000735

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000868

Hom.:

Bravo

AF:

0.0000302

EpiCase

AF:

0.000109

EpiControl

AF:

0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Ehlers-Danlos syndrome due to tenascin-X deficiency

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Lifecell International Pvt. Ltd	-	A Heterozygous Frameshift variant c.3290_3291delAA in Exon 8 of the TNXB gene that results in the amino acid substitution p.Lys1097fs*48 was identified. The observed variant has a minor allele frequency of 0.00002/0.00010 in gnomAD exomes and genomes, respectively. The severity of the impact of this variant on the protein is high, based on the effect of the protein and REVEL score . Rare Exome Variant Ensemble Learner (REVEL) is an ensembl method for predicting the pathogenicity of missense variants based on a combination of scores from 13 individual tools: MutPred, FATHMM v2.3, VEST 3.0, PolyPhen-2, SIFT, PROVEAN, MutationAssessor, MutationTaster, LRT, GERP++, SiPhy, phyloP, and phastCons. The REVEL score for an individual missense variant can range from 0 to 1, with higher scores reflecting greater likelihood that the variant is disease-causing. ClinVar has also classified this variant as Likely Pathogenic [Variant ID: 8550]. This mutation has been detected as homozygous in two individuals from an Ehlers-Danlos syndrome (EDS) cohort (Schalkwijk J et al. 2001). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 01, 2003	- -

TNXB-related disorder

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 13, 2024

The TNXB c.3290_3291delAA variant is predicted to result in a frameshift and premature protein termination (p.Lys1097Argfs*48). This variant has been reported to be pathogenic for autosomal recessive classical-like Ehlers-Danlos syndrome (EDS) (Fig. 4C of Schalkwijk et al. 2001. PubMed ID: 11642233). Of note, this variant has also been associated with hypermobility type EDS due to TNXB haploinsufficiency (reported as "[AA56063] del" in Zweers et al. 2003. PubMed ID: 12865992). This variant is reported in 0.0064% of alleles in individuals of European (Non-Finnish) descent in gnomAD. Frameshift variants in TNXB are expected to be pathogenic. This variant is interpreted as pathogenic. -

not provided

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Mar 30, 2022

In a Letter to the Editor from the authors of Schalkwijk et al. (2001), the group reports additional workup on the family members of their previous cohort; authors observed that heterozygous family members were found to have significantly reduced tenascin X levels with a female-skewed preponderance for joint hypermobility (Zweers et al., 2003); Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 26582918, 11642233, 12865992) -

Cardiovascular phenotype

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 10, 2019

The c.3290_3291delAA pathogenic mutation, located in coding exon 7 of the TNXB gene, results from a deletion of two nucleotides at nucleotide positions 3290 to 3291, causing a translational frameshift with a predicted alternate stop codon (p.K1097Rfs*48). This mutation has been detected as homozygous in two individuals from an Ehlers-Danlos syndrome (EDS) cohort (Schalkwijk J et al. N. Engl. J. Med., 2001 Oct;345:1167-75). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over