Customized Medicine for Corals

Coral reefs are facing unprecedented pressures, on a global scale.Alarming declines in coral abundance and diversity are occurring across the majority of reef systems, driven by the cumulative impacts of local stressors and rapidly changing climate (Hughes et al., 2017(Hughes et al., , 2018)).Increases in the greenhouse gas emission (GGE) rates are linked with marine heatwaves which cause mass coral bleaching events, a phenomenon reported as the main threat to coral reefs into the future (Sweet and Brown, 2016).The recent global coral bleaching event from 2014 to 2017 resulted in extensive mortality impacting reef functioning in ways not previously recorded (Eakin et al., 2019).The knock-on effects of this global environmental extreme are still playing out with recent assessment on the Great Barrier Reef (GBR) demonstrating drastic declines in coral recruitment, which may fundamentally change the ecosystem dynamics across this region into the future (Hughes et al., 2019).In addition, regional stressors such as overfishing, poor water quality, and pollution can also severely affect the health state of corals and reefs (Shaver et al., 2018).Most agree that the reduction of GGE rates is the priority to ensure the persistence of coral reef ecosystems, however under current GGE projections, annual mass coral bleaching events are expected to occur as early as 2050 (National Academies of Science, Engineering and National Academies of Sciences, 2018).Even if GGE emissions are significantly reduced, further decline of reef health appears unavoidable due to the current accumulation of greenhouse gases in the atmosphere and the predicted lag period before any change will be observed (Hoegh-Guldberg et al., 2007; National Academies of Sciences, 2018).This poses a major problem to those caring for and managing reef ecosystems.Coral bleaching events can be assessed through satellite monitoring of sea surface temperatures, however no effective mitigation strategies to lessen the impacts of bleaching on coral populations are currently available (National Academies of Sciences, 2018).While reducing GGE should be our focus, there is also an urgent need to move away from simply documenting the demise of coral reefs and explore options that can assist corals and build their resilience to the increasing number of threats they face.This is no trivial task and complicated further by the stochasticity of the environment across different regions with unique biotic and abiotic characteristics, including different cumulative impacts and threat levels posed.There is certainly no "magic recipe, " which can be applied on a global scale to reverse the declines in coral reef ecosystem health.However, the same principles that are applied to, and have improved human health, are relevant to the management of corals at the individual, population and ecosystem levels. EXPLORING THE "CUSTOMIZED MEDICINE" APPROACHAll organisms differ in their genotype and phenotype, with each individual's genetics, epigenetics, and associated microbiome critical to overall health status.In humans for example, each person contains a diverse set of traits that can make them either resilient or vulnerable to diseases and,