- Genes were clustered according to their expression patterns across all libraries containing H. defensa (except the heavily contaminated library H15R1) using two approaches, a correlation approach as described in Smith et al. [51] and weighted correlation network analysis (WGNA). The genes used for analysis were clustered into modules of co-expressed genes. These modules were tested for GO-term enrichment, for correlation with modules of another organism and for correlation with H. defensa titre