Pasquale Lucio Scandizzo and Alessandra Imperiali
University of Rome Tor Vergata

Genetic networks are recent paradigms for the inheritance of traits from parents. They can be defined as relational structures composed of genes, some of which carry genetic information, and linkages with structural or regulating properties. Previous studies have found that biological networks are characterized by scale-free or power-law algorithms, with the development of highly influential genes with many—but sparse—connections to other genes, and with key regulatory roles in phenotypical expression. The highly influential genes are “hotspots” of regulatory functions and represent the top of the network. Seven basic typologies of genetic networks have been discovered; in these networks, genes play different roles. In this article, we address the issue of the characteristics of genetic networks and their social and economic implications by reviewing recent literature on the subject and developing a meta-analysis of a sample of recent studies. We explore the implications of a model where the desirable traits depend not only on the properties of the individual genes, but also on their connections and the architecture of the network. The model suggests that under reasonable hypotheses and interpretations of past research, several important consequences follow for the interpretation of the roles of genes in everyday life, their interaction with the environment, and their socio-economic role. A major implication for agricultural research on biotechnology is that a strategy aimed to select varieties on the basis of topological properties of the underlying genetic network, and their regulatory role, may be more successful than one depending only on focusing on the direct association between specific genes and desirable traits.

Key words: Network analysis, co-expression networks, genetic networks.