Genetic Variant NM_001365276.2:c.2116_2117delGT (chr6-32095735-TAC-T) – ACMG Classification: Pathogenic (10 pts)

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1PM2

The NM_001365276.2(TNXB):c.2116_2117delGT(p.Val706ArgfsTer7) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,438 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

TNXB
NM_001365276.2 frameshift

Scores

Not classified

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 1.80

Publications

3 publications found

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 Gene-Disease associations (from GenCC):

Ehlers-Danlos syndrome
Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
Ehlers-Danlos syndrome due to tenascin-X deficiency
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Illumina, PanelApp Australia, Orphanet
familial vesicoureteral reflux
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
vesicoureteral reflux 8
Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

TNXB links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 10 ACMG points.

PVS1

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

PM2

Very rare variant in population databases, with high coverage;

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001365276.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TNXB	NM_001365276.2	MANE Select	c.2116_2117delGT	p.Val706ArgfsTer7	frameshift	Exon 3 of 44	NP_001352205.1
TNXB	NM_001428335.1		c.2116_2117delGT	p.Val706ArgfsTer7	frameshift	Exon 3 of 45	NP_001415264.1
TNXB	NM_019105.8		c.2116_2117delGT	p.Val706ArgfsTer7	frameshift	Exon 3 of 44	NP_061978.6

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TNXB	ENST00000644971.2	MANE Select	c.2116_2117delGT	p.Val706ArgfsTer7	frameshift	Exon 3 of 44	ENSP00000496448.1
TNXB	ENST00000479795.1	TSL:1	c.2116_2117delGT	p.Val706ArgfsTer7	frameshift	Exon 3 of 5	ENSP00000418248.1
TNXB	ENST00000486148.1	TSL:1	n.2511_2512delGT		non_coding_transcript_exon	Exon 2 of 2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD2 exomes

AF:

0.0000243

AC:

AN:

246568

AF XY:

0.0000224

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000291

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000270

Gnomad OTH exome

AF:

0.000333

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461438

Hom.:

AF XY:

0.00000138

AC XY:

AN XY:

727038

show subpopulations

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

33472

American (AMR)

AF:

0.00

AC:

AN:

44716

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39696

South Asian (SAS)

AF:

0.00

AC:

AN:

86240

European-Finnish (FIN)

AF:

0.0000187

AC:

AN:

53370

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5764

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1111676

Other (OTH)

AF:

0.00

AC:

AN:

60368

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.225

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

Cov.:

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

PhyloP100

1.8

Mutation Taster

=4/196

disease causing (fs/PTC)

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

ClinVar

Computational scores

Splicing

Publications

Other links and lift over