Total submissions: 3
Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
---|---|---|---|---|---|---|---|---|
Laboratory for Molecular Medicine, |
RCV000040119 | SCV000063810 | uncertain significance | not specified | 2012-03-14 | criteria provided, single submitter | clinical testing | Variant classified as Uncertain Significance - Favor Pathogenic. The 27694+1G>C variant in TTN has not been previously identified by our laboratory but is liste d in dbSNP (rs6749719) without frequency information. This variant is predicted to cause abnormal splicing because the nucleotide substitution occurs in the hig hly conserved splice consensus sequence resulting in an abnormal or absent prote in. Loss-of-function variants in TTN are common in patients with DCM (Herman 201 2), though their role in HCM is unclear. In addition, variants in TTN are also associated with several myopathies (Hackman 2002, Hackman 2008, www.OMIM.org). A lthough this variant is predicted to have a severe impact on the protein, additi onal studies are needed to determine if this is contributes to this patient's cl inical features. |
Cardiovascular Biomedical Research Unit, |
RCV000209261 | SCV000189730 | uncertain significance | 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 with intermediate levels of cardiac expression. 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. |
Invitae | RCV000560902 | SCV000642967 | uncertain significance | Dilated cardiomyopathy 1G; Autosomal recessive limb-girdle muscular dystrophy type 2J | 2023-09-08 | criteria provided, single submitter | clinical testing | In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This variant is located in the I band of TTN (PMID: 25589632). Truncating variants in this region have been shown to be highly prevalent in the general population and unaffected individuals (PMID: 26701604, 22335739). However, truncating variants in this region have also been reported in individuals affected with autosomal recessive centronuclear myopathy (PMID: 23975875). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 46849). Disruption of this splice site has been observed in individual(s) with dilated cardiomyopathy (PMID: 25589632). This variant is present in population databases (rs6749719, gnomAD 0.002%). This sequence change affects a donor splice site in intron 117 of the TTN gene. It is expected to disrupt RNA splicing and likely results in a truncated or disrupted TTN protein. |