Total submissions: 6
Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
---|---|---|---|---|---|---|---|---|
Cardiovascular Biomedical Research Unit, |
RCV000208904 | SCV000189697 | likely pathogenic | Primary dilated cardiomyopathy | 2014-10-08 | criteria provided, single submitter | research | This TTN truncating variant (TTNtv) was identified in one individual in this cohort and is located in an exon that is highly expressed in the heart. In the seven cohorts assessed, TTNtv were found in 14% of ambulant DCM, 22% end-stage or familial DCM, and 2% controls. Heterozygous nonsense, frameshift and canonical splice-disrupting variants found in constitutive and other highly utilised exons are highly likely to be pathogenic when identified in individuals with phenotypically confirmed DCM. TTNtv found incidentally in healthy individuals (excluding familial assessment of DCM relatives) are thought to have low penetrance, particularly when identified in exons that are not constitutively expressed in the heart. |
Gene |
RCV000184261 | SCV000236883 | pathogenic | not provided | 2023-01-23 | criteria provided, single submitter | clinical testing | Identified in a patients with DCM in the published literature (Roberts et al., 2015; Stava et al., 2022); Not observed at significant frequency in large population cohorts (gnomAD); Nonsense 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; Located in the A-band region of titin, where the majority of truncating pathogenic variants associated with DCM have been reported (Herman et al., 2012).; This variant is associated with the following publications: (PMID: 34135346, 35653365, 22335739, 25589632) |
Labcorp Genetics |
RCV001381840 | SCV001580382 | pathogenic | Dilated cardiomyopathy 1G; Autosomal recessive limb-girdle muscular dystrophy type 2J | 2023-10-15 | criteria provided, single submitter | clinical testing | This sequence change creates a premature translational stop signal (p.Arg24780*) in the TTN gene. While this is not anticipated to result in nonsense mediated decay, it is expected to create a truncated TTN protein. This variant is present in population databases (rs794729285, gnomAD 0.0009%). This premature translational stop signal has been observed in individuals with dilated cardiomyopathy (PMID: 25589632; Invitae). ClinVar contains an entry for this variant (Variation ID: 202405). This variant is located in the A band of TTN (PMID: 25589632). Truncating variants in this region are significantly overrepresented in patients affected with dilated cardiomyopathy (PMID: 25589632). Truncating variants in this region have also been reported in individuals affected with autosomal recessive centronuclear myopathy (PMID: 23975875). For these reasons, this variant has been classified as Pathogenic. |
Ambry Genetics | RCV002336472 | SCV002637690 | likely pathogenic | Cardiovascular phenotype | 2019-07-29 | criteria provided, single submitter | clinical testing | The p.R15715* variant (also known as c.47143C>T), located in coding exon 153 of the TTN gene, results from a C to T substitution at nucleotide position 47143. This changes the amino acid from an arginine to a stop codon within coding exon 153. This exon is located in the A-band region of the N2-B isoform of the titin protein and is constitutively expressed in TTN transcripts (percent spliced in or PSI 100%). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. While truncating variants in TTN are present in 1-3% of the general population, truncating variants in the A-band are the most common cause of dilated cardiomyopathy (DCM) (Herman DS et al. N. Engl. J. Med. 2012 Feb;366:619-28; Roberts AM et al. Sci Transl Med. 2015 Jan;7:270ra6). TTN truncating variants encoded in constitutive exons (PSI >90%) have been found to be significantly associated with DCM regardless of their position in titin (Schafer S et al. Nat. Genet. 2017 Jan;49:46-53). As such, this alteration is classified as likely pathogenic. |
Fulgent Genetics, |
RCV002503724 | SCV002815802 | pathogenic | Dilated cardiomyopathy 1G; Autosomal recessive limb-girdle muscular dystrophy type 2J; Tibial muscular dystrophy; Myopathy, myofibrillar, 9, with early respiratory failure; Early-onset myopathy with fatal cardiomyopathy; Hypertrophic cardiomyopathy 9 | 2021-10-02 | criteria provided, single submitter | clinical testing | |
Cardiogenetics and Myogenetics Molecular and Cellular Functional Unit, |
RCV004764909 | SCV005374985 | pathogenic | Dilated cardiomyopathy 1G | 2024-01-06 | no assertion criteria provided | clinical testing |