Summary

Genetic testing in inherited arrhythmias (IAs) and cardiomyopathies (CMs) is a published guideline recommendation, as identifying the underlying molecular cause for disease can guide treatment, surveillance, and even determine clinical trial eligibility. Studies documenting the yield of genetic testing in cohorts of patients with suspected IAs and CMs have not routinely included both nuclear and mitochondrial DNA (mtDNA) genes. To highlight the utility of this testing, we reviewed results from 1,883 patients with a clinical suspicion of IA and/or CM, having received the Blueprint Genetics’ combined IA and CM next-generation sequencing (NGS) panel, which included sequencing and copy number variant (CNV) analysis, of both nuclear and mtDNA genes. Key findings include that

• >1 in 6 of patients received an informative result 

• CNVs and noncoding variants explained ~6% of informative results,  

• Among patients who had the mitochondrial genome included, mtDNA variants accounted for 2.4% of informative results 

• Children had a higher yield of testing (22.9%) than adults (16.6%). 

This work supports the inclusion of both nuclear and mtDNA genes in genetic testing of patients with IA and/or CM as this approach may increase the yield of testing and enable precise management of affected individuals 

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Authors:

Julie Hathaway, Johanna Huusko, Marcos Cicerchia, Saija Ahonen, Johanna Tommiska, Kimberly Gall, Khalida Liaquat, Victoria Howell, Allison Sluyters, Janica Djupsjöbacka, Mikko Muona, Inka Saarinen, Eija Seppälä, Tiia Kangas-Kontio, Lotta Koskinen, Pertteli Salmenperä, Samuel Myllykangas, Juha Koskenvuo   

  References:

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