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Sudden cardiac death (SCD) is a major cause of death in industrial countries. Although SCD occurs mainly in adults, it may also affect young persons, where genetic cardiac disorders comprise at least half of these cases. This includes primary arrhythmogenic disorders such as long QT syndrome and inherited cardiomyopathies. However, in many cases, postmortem examinations provide no conclusive results explaining the cause of death. Since family members of the deceased may eventually have inherited the same disease, they are at risk of SCD. In the present study, 28 patients with a family history of sudden unexplained death (SUD), of survived cardiac arrest and with a clinical diagnosis of an inherited cardiac disease were screened using phenotype-guided molecular analysis of genes associated with arrhythmogenic cardiac diseases. In 64% of the cases, gene variants with potentially pathogenic cardiac effects were detected suggesting that an arrhythmia syndrome may have caused the death of the deceased family member. Therefore, we recommend that relatives of SUD victims should undergo extended cardiac examination and, depending on the clinical diagnosis, a targeted genetic analysis should follow, which is crucial to identify family members at risk., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Selective inhibition of disease-related proteins underpins the majority of successful drug-target interactions. However, development of effective antagonists is often hampered by targets that are not druggable using conventional approaches. Here, we apply engineered zinc-finger protein transcription factors (ZFP TFs) to the endogenous phospholamban (PLN) gene, which encodes a well validated but recalcitrant drug target in heart failure. We show that potent repression of PLN expression can be achieved with specificity that approaches single-gene regulation. Moreover, ZFP-driven repression of PLN increases calcium reuptake kinetics and improves contractile function of cardiac muscle both in vitro and in an animal model of heart failure. These results support the development of the PLN repressor as therapy for heart failure, and provide evidence that delivery of engineered ZFP TFs to native organs can drive therapeutically relevant levels of gene repression in vivo. Given the adaptability of designed ZFPs for binding diverse DNA sequences and the ubiquity of potential targets (promoter proximal DNA), our findings suggest that engineered ZFP repressors represent a powerful tool for the therapeutic inhibition of disease-related genes, therefore, offering the potential for therapeutic intervention in heart failure and other poorly treated human diseases.

Zinc finger protein transcription factors (ZFP TFs) have been shown to positively or negatively regulate the expression of endogenous genes involved in a number of different disease processes. In this study we investigated whether gene transfer of an engineered ZFP TF designed to up-regulate expression of the chromosomal pigment epithelium-derived factor (Pedf) gene could suppress experimentally induced choroidal neovascularization (CNV). Transient transfection with engineered ZFP TFs significantly increased both Pedf messenger RNA (mRNA) and secreted PEDF protein levels in cell culture. Six weeks after intravitreous or subretinal injection of an adeno-associated viral (AAV) vector expressing the PEDF-activating ZFP TF in mice, we observed increased retinal Pedf mRNA, and a significant reduction in the size of CNV at Bruch's membrane rupture sites, assessed in vivo by fluorescein angiography or by postmortem measurements on choroidal flat mounts. Importantly, the anti-angiogenic activity persisted at 3 months after intravitreous injection. These data suggest that ZFP TF-driven enhancement of the endogenous anti-angiogenic defense system may provide a new approach for prophylaxis and treatment of neovascular diseases of the eye.