In fact, after analyzing the expression profiles in a sample of 73 healthy tissues, only 16 (or 9.64%) gene-pairs show a completely divergent pattern of gene-expression (coexpression value ≤ 0.2, see Methods), while 13 (or 7.83%) exhibit complete coexpression (coexpression value = 1).
The others show divergent patterns of gene expression.
Conversely, paralogs with r < 0.78 were considered to have developed divergent patterns of gene expression.
Polyploidy has clearly been an important source of genetic variation across the angiosperms as retained duplicate genes typically show divergent patterns of gene expression [ 85, 86].
This proportion of genes showing divergent patterns of gene expression seemed to be consistent with estimates made for other species with proportions usually ranging from 74% to 85% [ 13, 20, 61, 62].
For this, an enrichment analysis of GO terms was performed between, the group of paralog genes showing divergent patterns of gene expression and the group of duplicates showing co-regulated expression profiles.
Thus, for the 34 genes examined in this study, the lack of variation in proximal promoter sequence between the two genesets implicates alternative sources for divergent patterns of gene expression.
Furthermore, as illustrated by the divergent patterns of gene expansion and expression revealed in our analyses, independently evolved social lineages often explore different subsets of chemoreceptors for their communication.
The evolution of duplicated genes by developing divergent patterns of gene expression has been suggested to be a first step in this process, allowing the partition of gene function (subfunctionalization), thus favouring gene retention and ultimately creating the conditions for neofunctionalization [ 60, 61].
