Genetic Variant NM_003673.4:c.157C>T (chr17-39665762-C-T) – ACMG Classification: Pathogenic (14 pts)

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_003673.4(TCAP):c.157C>T(p.Gln53*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,610,334 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

TCAP
NM_003673.4 stop_gained

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 1.95

Variant links:

Genes affected

TCAP (HGNC:11610): (titin-cap) Sarcomere assembly is regulated by the muscle protein titin. Titin is a giant elastic protein with kinase activity that extends half the length of a sarcomere. It serves as a scaffold to which myofibrils and other muscle related proteins are attached. This gene encodes a protein found in striated and cardiac muscle that binds to the titin Z1-Z2 domains and is a substrate of titin kinase, interactions thought to be critical to sarcomere assembly. Mutations in this gene are associated with limb-girdle muscular dystrophy type 2G. [provided by RefSeq, Jul 2008]

TCAP links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 16 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 17-39665762-C-T is Pathogenic according to our data. Variant chr17-39665762-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 5525.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-39665762-C-T is described in Lovd as [Pathogenic]. Variant chr17-39665762-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TCAP	NM_003673.4 link	c.157C>T	p.Gln53*	stop_gained	Exon 2 of 2	ENST00000309889.3	NP_003664.1	O15273A2TDC0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TCAP	ENST00000309889.3 link	c.157C>T	p.Gln53*	stop_gained	Exon 2 of 2	1	NM_003673.4	ENSP00000312624.2		O15273
TCAP	ENST00000578283.1 link	c.157C>T	p.Gln53*	stop_gained	Exon 2 of 3	5		ENSP00000462787.1		J3KT40

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152164

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1458170

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

725214

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:

9.00e-7

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152164

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74338

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2G

Pathogenic:2

Jan 05, 2022

DASA

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.157C>T;p.(Gln53*) variant creates a premature translational stop signal in the TCAP gene. It is expected to result in an absent or disrupted protein product -PVS1_strong. This sequence change has been observed in affected individual(s) and ClinVar contains an entry for this variant (ClinVar ID: 5525; PMID: 10655062; PMID: 27618135; PMID: 25298746) - PS4. The variant is present at low allele frequencies population databases (rs104894655 – gnomAD 0.001314%; ABraOM 0.001281 frequency - http://abraom.ib.usp.br/) -PM2_supporting. In summary, the currently available evidence indicates that the variant is pathogenic. -

Feb 01, 2000

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Primary dilated cardiomyopathy

Pathogenic:1

Oct 09, 2009

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Hypertrophic cardiomyopathy 25

Pathogenic:1

Laboratory of Genetics and Molecular Cardiology, University of São Paulo

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Primary familial hypertrophic cardiomyopathy;C4225408:Hypertrophic cardiomyopathy 25

Pathogenic:1

Jan 06, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Gln53*) in the TCAP gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 115 amino acid(s) of the TCAP protein. This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individuals with autosomal recessive limb-girdle muscular dystrophy (PMID: 10655062, 23479141, 25298746). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 5525). For these reasons, this variant has been classified as Pathogenic. -

Autosomal recessive limb-girdle muscular dystrophy type 2G;C4225408:Hypertrophic cardiomyopathy 25

Pathogenic:1

Aug 31, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.58

BayesDel_noAF

Pathogenic

0.50

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

0.80

Eigen_PC

Uncertain

0.63

FATHMM_MKL

Uncertain

0.88

Vest4

0.74

GERP RS

3.6

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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