Oyster Disease Research Program: Building Gene Expression-Based Predictors of Oyster Summer Mortality Syndrome

Pacific oyster (Crassostrea gigas) fisheries on the U.S. West Coast, Mexico, France and Japan, are significantly impacted by high rates of oyster mortality in the summer months, in California ranging from 52-63%. This summer mortality syndrome (SMS) occurs predominantly in near-market ready oysters and seems to impact reproductive females the most. There is an urgent need for studies to investigate the metabolic and molecular basis of the syndrome, with the goal of identifying, and then producing summer mortality-resistant stocks. The specific hypotheses that we are testing is that changes in hemocyte gene expression could be used as a predictor of the onset of summer mortality, and that these changes in gene expression could be used as a predictor of the onset of the syndrome as well as providing insights into the pathophysiological basis of the disease