Synthetic genetic circuits in crop plants.

The love affair between crop breeding and genetics began over a century ago and has continued unabated, from mass selection programs to targeted genome modifications. Synthetic genetic circuits, a recent development, are combinations of regulatory and coding DNA introduced into a crop plant to achieve a desired function. Genetic circuits could accelerate crop improvement, allowing complex traits to be rationally designed and requisite DNA parts delivered directly into a genome of interest. However, there is not yet a standardized pipeline from exploratory laboratory testing to crop trials, and bringing transgenic products to market remains a considerable barrier. We highlight successes so far and future developments necessary to make genetic circuits a viable crop improvement technology over this century.