Submissions for variant NM_001267550.2(TTN):c.107351C>G (p.Ser35784Ter)

dbSNP: rs1575185742

Total submissions: 2

Submitter	RCV	SCV	Clinical significance	Condition	Last evaluated	Review status	Method	Comment
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard	RCV001004968	SCV001164507	pathogenic	Autosomal recessive limb-girdle muscular dystrophy type 2J	2018-12-03	criteria provided, single submitter	research	The heterozygous p.Ser35784Ter variant in TTN was identified by our study in the compound heterozygous state, with another pathogenic variant, in one individual with limb-girdle muscular dystrophy (LGMD). The presence of this variant in combination with a pathogenic variant and in an individual with LGMD increases the likelihood that the p.Ser35784Ter variant is pathogenic. This variant was absent from large population studies. This nonsense variant leads to a premature termination codon at position 35784, which is predicted to lead to a truncated or absent protein. Loss of function of the TTN gene is an established disease mechanism in autosomal recessive LGMD. In summary, this variant meets criteria to be classified as pathogenic for LGMD in an autosomal recessive manner based on the predicted impact of the variant and the presence of a pathogenic variant in an individual with LGMD. ACMG/AMP Criteria applied: PM2, PVS1, PM3 (Richards 2015).
Labcorp Genetics (formerly Invitae), Labcorp	RCV003769409	SCV004605212	likely pathogenic	Dilated cardiomyopathy 1G; Autosomal recessive limb-girdle muscular dystrophy type 2J	2024-01-22	criteria provided, single submitter	clinical testing	This sequence change creates a premature translational stop signal (p.Ser35784*) 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 not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TTN-related conditions. ClinVar contains an entry for this variant (Variation ID: 813975). This variant is located in the M band of TTN (PMID: 25589632). Truncating variants in this region have been previously reported in individuals affected with autosomal recessive myopathy and muscular dystrophy (PMID: 18948003, 23975875, 24395473). Truncating variants in this region have also been identified in individuals affected with autosomal dominant dilated cardiomyopathy and/or cardio-related conditions (PMID: 27869827, 32964742, Invitae internal data). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic.