In considering a model with both main and interaction effects of behavioral category, expression level, and connectivity, connectivity had the strongest effect (glm with quasibinomial residuals: t = 24.5, p < 10−16, for the presence of S. invicta orthologs; t = 32.2, p < 10−16, for the presence of A. mellifera orthologs), with more highly connected genes being more likely to have an ortholog.
The reason for the observation that named genes have a higher degree is not clear given that it is both possible that known genes are indeed better studied and thus have an artificially high degree or that more highly connected genes are mutable to more obvious phenotypes and thus become detected in genetic studies more often and then named.
We assumed that the more functionally connected genes have the greater number of interactions between them.
Another difference is that the Rank product produces more highly connected genes which have been shown in the literature to be regulated by ERα, than GEMS.
These observations led to the development of the gene balance hypothesis, which predicts that more highly connected genes should tend to be retained following WGD because of purifying selection for stoichiometric balance among interaction proteins [ 29].
It was shown that functionally connected genes have more connections between each other than randomly selected genes.
It is widely accepted that hub genes are more essential than poorly connected genes.
More importantly, the top connected genes in the black module (kME >0.7) significantly overlapped with a previously defined co-expression module, called asdM12, identified via unbiased transcriptome analysis in postmortem ASD brains (OR = 2.4, P = 0.02) [ 33], but not preserved in control tissues.
These studies have shown that highly connected genes are more likely to be essential [ 4, 7] and have a tendency toward having a more deleterious effect on growth rate when deleted [ 5, 8].
