Submissions for variant NM_001267550.2(TTN):c.76739C>A (p.Thr25580Lys)

dbSNP: rs56372592

Total submissions: 13

Submitter	RCV	SCV	Clinical significance	Condition	Last evaluated	Review status	Method	Comment
Biesecker Lab/Clinical Genomics Section, National Institutes of Health	RCV000172636	SCV000054935	likely benign	not provided	2013-06-24	criteria provided, single submitter	research
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	RCV000214788	SCV000272763	uncertain significance	not specified	2015-03-20	criteria provided, single submitter	clinical testing	The p.Thr23012Lys variant in TTN has not been identified in individuals with car diomyopathy but has been identified in 21/66636 European chromosomes by the Exom e Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs56372592 . Computational prediction tools and conservation analysis do not provide strong support for or against an impact to the protein. In summary, the clinical signi ficance of the p.Thr23012Lys variant is uncertain.
Invitae	RCV000467029	SCV000542252	uncertain significance	Dilated cardiomyopathy 1G; Autosomal recessive limb-girdle muscular dystrophy type 2J	2017-10-26	criteria provided, single submitter	clinical testing
Illumina Laboratory Services, Illumina	RCV001135365	SCV001295142	uncertain significance	Dilated cardiomyopathy 1G	2018-01-13	criteria provided, single submitter	clinical testing	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease.
Illumina Laboratory Services, Illumina	RCV001135366	SCV001295143	uncertain significance	Autosomal recessive limb-girdle muscular dystrophy type 2J	2018-01-13	criteria provided, single submitter	clinical testing	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease.
Illumina Laboratory Services, Illumina	RCV001135367	SCV001295144	uncertain significance	Early-onset myopathy with fatal cardiomyopathy	2018-01-13	criteria provided, single submitter	clinical testing	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease.
Illumina Laboratory Services, Illumina	RCV001135368	SCV001295145	benign	Tibial muscular dystrophy	2018-01-13	criteria provided, single submitter	clinical testing	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease.
Illumina Laboratory Services, Illumina	RCV001135369	SCV001295146	benign	Myopathy, myofibrillar, 9, with early respiratory failure	2018-01-13	criteria provided, single submitter	clinical testing	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease.
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario	RCV001798622	SCV002042985	likely benign	Cardiomyopathy	2019-09-23	criteria provided, single submitter	clinical testing
Ambry Genetics	RCV002336416	SCV002643930	likely benign	Cardiovascular phenotype	2019-05-29	criteria provided, single submitter	clinical testing	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.
Revvity Omics, Revvity	RCV000172636	SCV003819768	uncertain significance	not provided	2022-08-16	criteria provided, single submitter	clinical testing
Women's Health and Genetics/Laboratory Corporation of America, LabCorp	RCV000214788	SCV003934113	uncertain significance	not specified	2023-05-08	criteria provided, single submitter	clinical testing	Variant summary: TTN c.69035C>A (p.Thr23012Lys) results in a non-conservative amino acid change located in the A-band region of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00021 in 279410 control chromosomes (gnomAD), predominantly at a frequency of 0.00038 within the Non-Finnish European subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in TTN causing Dilated Cardiomyopathy (0.00021 vs 0.00039), allowing no conclusion about variant significance. c.69035C>A has been reported in the literature in individuals with Hypertrophic Cardiomyopathy without strong evidence for causality (Lopes_2013). This report does not provide unequivocal conclusions about association of the variant with Dilated Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 23396983). Seven ClinVar submitters have assessed the variant since 2014: four classified the variant as uncertain significance, two as likely benign, and one as benign. Based on the evidence outlined above, the variant was classified as uncertain significance.
GeneDx	RCV000172636	SCV000237557	not provided	not provided	2014-04-02	no assertion provided	clinical testing	Missense variants in the TTN gene are considered 'unclassified' if they are not previously reported in the literature and do not have >1% frequency in the population to be considered a polymorphism. Research indicates that truncating mutations in the TTN gene are expected to account for approximately 25% of familial and 18% of sporadic idiopathic DCM; however, truncating variants in the TTN gene have been reported in approximately 3% of reported control alleles. There has been little investigation into non-truncating variants. (Herman D et al. Truncations of titin causing dilated cardiomyopathy. N Eng J Med 366:619-628, 2012) The variant is found in CARDIOMYOPATHY panel(s).