The primary focus of Andrew Gracey's research is to understand the effect of factors such as temperature, oxygen concentration, and salinity on the physiological processes of animals, and how these organism-environment interactions affect performance, survival and distribution. His studies explore the nature of adaptive responses and the evolutionary development of stress tolerance in a range of species spanning multiple phyla, including freshwater and marine fish, nematode worms, bivalve mollusks and hibernating mammals. Since phenotype results ultimately from the combined expression of genes and gene complexes, understanding patterns of gene expression evoked during environmental change yields insights regarding the mechanisms underlying adaptation from the cellular to the whole organism level. A key tool deployed in his research is the measurement of mRNA transcript levels by microarray hybridization. The microarray-based approach monitors the expression of many thousands of genes simultaneously, providing a broad view of the transcriptional changes that accompany alterations in physiological state. The utility of this approach is that it allows hitherto unknown responses to be discovered and new hypotheses to be formed. The identification of differentially expressed genes in response to environmental change is thus an important first step in understanding the role of the genome within the complex natural history of an organism.
