An essay on the necessity and feasibility of conservation genomics

The basic premise of conservation genetics is that small populations may be genetically threatened. The two steps leading to this premise are: (1) due to prominent influence of random genetic drift and inbreeding allelic and genotypic diversity in small populations is expected to be low, and (2) low allelic diversity and high homozygosity are expected to lead to immediate fitness decreases (inbreeding depression) and a compromised potential for evolutionary adaptation. Conservation genetic research has been strongly stimulated by the application of neutral molecular markers like microsatellites and AFLPs. In general these marker studies have provided evidence for step 1. It is less evident how these markers may provide evidence for step 2. In this essay we argue that, in order to get detailed insight in step 2, adopting a conservation genomic approach, in which conservation genetics will use approaches from ecological and evolutionary functional genomics (ecogenomics), is both necessary and feasible. Conservation genomics is necessary for studying functional genomic variation as function of drift and inbreeding, for studying the mechanisms that relate low genetic variation to low fitness, for integrating environmental and genetic approaches to conservation biology, and for developing modern, fast monitoring tools. The rapid technical and financial developments in genomics currently make conservation genomics feasible, and will improve feasibility in the very near future even further. We therefore argue that conservation genomics personifies part of the near future of conservation genetics.