Total submissions: 2
| Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
|---|---|---|---|---|---|---|---|---|
| Ambry Genetics | RCV002336044 | SCV002644666 | pathogenic | Cardiovascular phenotype | 2021-02-10 | criteria provided, single submitter | clinical testing | The c.51145_51154del10 pathogenic mutation, located in coding exon 153 of the TTN gene, results from a deletion of 10 nucleotides at nucleotide positions 51145 to 51154, causing a translational frameshift with a predicted alternate stop codon (p.Y17049Efs*3). 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 variant has been detected in an individual reported to have heart failure with significantly reduced ejection fraction and family history of heart failure (Ambry internal data). 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 01;49:46-53). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. |
| Victorian Clinical Genetics Services, |
RCV004785604 | SCV005399228 | likely pathogenic | Dilated cardiomyopathy 1G | 2024-09-19 | criteria provided, single submitter | clinical testing | Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Likely Pathogenic. Following criteria are met: 0102 - Loss of function is known mechanism of disease in this gene. In addition, dominant-negative is also a suggested mechanism. (PMID: 25589632). (I) 0108 - This gene is associated with both recessive and dominant disease (OMIM). (I) 0112 - The condition associated with this gene has incomplete penetrance. Variants in this gene that result in a premature termination codon (PTC) are known to have reduced penetrance in DCM (PMID: 25589632). (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0600 - Variant is located in the annotated A-band domain, with an exon PSI score of 100% (cardiodb, PMID: 25589632). (I) 0702 - Other NMD-predicted variants comparable to the one identified in this case have strong previous evidence for pathogenicity (DECIPHER). (SP) 0803 - This variant has limited previous evidence of pathogenicity in an unrelated individual. This variant has been classified as pathogenic in ClinVar. (SP) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign |