Submissions for variant NM_001267550.2(TTN):c.5875T>A (p.Phe1959Ile)

dbSNP: rs562856820

Total submissions: 13

Submitter	RCV	SCV	Clinical significance	Condition	Last evaluated	Review status	Method	Comment
Labcorp Genetics (formerly Invitae), Labcorp	RCV001087650	SCV000555137	benign	Dilated cardiomyopathy 1G; Autosomal recessive limb-girdle muscular dystrophy type 2J	2025-01-29	criteria provided, single submitter	clinical testing
Athena Diagnostics	RCV000516843	SCV000616112	benign	not specified	2017-04-12	criteria provided, single submitter	clinical testing
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario	RCV001170109	SCV001332648	benign	Cardiomyopathy	2018-03-14	criteria provided, single submitter	clinical testing
Women's Health and Genetics/Laboratory Corporation of America, LabCorp	RCV000516843	SCV001372371	benign	not specified	2020-06-15	criteria provided, single submitter	clinical testing	Variant summary: TTN c.5875T>A (p.Phe1959Ile) results in a non-conservative amino acid change in 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 0.001 in 251176 control chromosomes, predominantly at a frequency of 0.0081 within the South Asian subpopulation in the gnomAD database, including 5 homozygotes. The observed variant frequency within South Asian control individuals in the gnomAD database is approximately 13 fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Cardiomyopathy phenotype (0.00063), strongly suggesting that the variant is a benign polymorphism found primarily in populations of South Asian origin. To our knowledge, no occurrence of c.5875T>A in individuals affected with Cardiomyopathy and no experimental evidence demonstrating its impact on protein function have been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as benign. Based on the evidence outlined above, the variant was classified as benign.
Genome-Nilou Lab	RCV001840311	SCV002101465	benign	Autosomal recessive limb-girdle muscular dystrophy type 2J	2021-09-10	criteria provided, single submitter	clinical testing
Genome-Nilou Lab	RCV001840312	SCV002101466	benign	Myopathy, myofibrillar, 9, with early respiratory failure	2021-09-10	criteria provided, single submitter	clinical testing
Genome-Nilou Lab	RCV001840313	SCV002101467	benign	Early-onset myopathy with fatal cardiomyopathy	2021-09-10	criteria provided, single submitter	clinical testing
Genome-Nilou Lab	RCV001840310	SCV002101469	benign	Tibial muscular dystrophy	2021-09-10	criteria provided, single submitter	clinical testing
Ambry Genetics	RCV002345665	SCV002650237	benign	Cardiovascular phenotype	2019-06-14	criteria provided, single submitter	clinical testing	This alteration is classified as 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.
GeneDx	RCV000185176	SCV000238016	not provided	not provided	2014-08-08	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 DCM-CRDM panel(s).
Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)	RCV000185176	SCV001797604	likely benign	not provided		no assertion criteria provided	clinical testing
Clinical Genetics, Academic Medical Center	RCV000516843	SCV001918709	benign	not specified		no assertion criteria provided	clinical testing
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	RCV000516843	SCV001972508	benign	not specified		no assertion criteria provided	clinical testing