While the contribution of exposure of future fathers (paternal) to environmental factors, such as smoking, to the pathogenesis of several disease states has been documented, that of Electronic Nicotine Delivery Systems (ENDS), including in the context of occlusive cardiovascular disease (CVD), has not yet been investigated. Therefore, the present application proposes experiments that address fundamental, mechanistic, and clinically- relevant translational aspects of the adverse-health effects of ENDS, namely e-waterpipes and e-cigarettes, which are increasingly popular forms of tobacco, in the context of paternal exposure on thrombotic disease and platelet biology. These studies will be performed in a sex-dependent fashion. Specifically, the ramifications of ENDS paternal exposure on normal hemostasis and the development of thrombosis disease will be determined. Subsequent studies will examine whether ENDS modulate platelet function and/or counts. Experiments are also designed to determine the effects of ENDS on clotting/thrombosis markers and the coagulation system. We will also investigate if their effects involve inflammation and non-platelet cells (e.g., endothelial cells and neurtophils). In addition, and in terms of the mechanistic experiments, the role of the platelet transcriptome (e.g., miRnome) of the offspring and the epigenetic marks (e.g., histone modification) of the father's sperm in mediating ENDS paternal effects will be determined. Finally, the impact of paternal ENDS on the placenta and the sperm non- coding RNA will also be investigated. Collectively, these experiments will make significant contributions to the understanding of the consequences of paternal ENDS exposure- an increasingly popular and underappreciated health threat- on cardiovascular health, as well as the mechanism by which it exerts these effects, in a sex- specific manner.