TTR variants in HCM cohorts

The table below lists the 2 rare (MAF<0.0001 in ExAC) protein-altering TTR variants identified in a cohort of 632 HCM patients. When this rare variant frequency of 0.00316 is compared with a background population rate of 0.00140, there is a case excess of 0.00176, although this is not statistically significant for protein-altering TTR variants in HCM (p=0.2264).

Variant Type:      All protein-altering variants     -     Truncating variants     -     Non-Truncating variants
Source:      LMM

No. Variant (CDS) Variant (Protein) Variant Type Cases (632)LMM class ExAC frequency
1. c.190T>C p.F64Lmissense 1VUS favour pathogenic (1)0.000057
2. c.385G>A p.A129Tmissense 1VUS (1)0.000049


1. Roddy Walsh, Kate L. Thomson, James S. Ware, Birgit H. Funke, Jessica Woodley, Karen J. McGuire, Francesco Mazzarotto, Edward Blair, Anneke Seller, Jenny C. Taylor, Eric V. Minikel, Exome Aggregation Consortium, Daniel G. MacArthur, Martin Farrall, Stuart A. Cook and Hugh Watkins. Reassessment of Mendelian gene pathogenicity using 7,855 cardiomyopathy cases and 60,706 reference samples. Genet Med. 2016 doi:10.1038/gim.2016.90.

2. Alfares AA, Kelly MA, McDermott G, Funke BH, Lebo MS, Baxter SB, Shen J, McLaughlin HM, Clark EH, Babb LJ, Cox SW, DePalma SR, Ho CY, Seidman JG, Seidman CE, Rehm HL. Results of clinical genetic testing of 2,912 probands with hypertrophic cardiomyopathy: expanded panels offer limited additional sensitivity. Genet Med. 2015 Nov;17(11):880-8.