Functional genetics and genomics in ants (Hymenoptera: Formicidae): The interplay of genes and social life

Abstract

Ants are among the most remarkable and successful of animal taxa. The success of ants stems from their complex social systems, which originate, in part, from the genetic composition of individual society members. In this review, we evaluate progress in understanding how genetic information influences complex phenotypes in ants. We find that research on the structure of ant genomes has been strong in some areas, such as the exploration of chromosome number, genome size, and karyotype evolution. However, other areas of structural genomics concerned with gene number and genome content remain poorly studied. We also find that substantial progress has been made in successfully documenting genetic effects on phenotypic variation associated with ant social structure. For example, genetic variation influences sex determination in some ants and is associated with caste determination in several species. In addition, direct genetic control of queen and worker phenotypes has been discovered in some ant taxa. Advances have also been made in identifying genes whose patterns of expression are associated with ant social structure, development, and caste differentiation. Sufficient data are now available to address important questions regarding the relationship between the evolution of gene expression and phenotype. Finally, we review for the first time the growing sociogenomics literature in ants aimed at addressing the molecular bases for social life. Overall, substantial progress has been made in linking molecular genetic information to phenotypic variation in ants. However, many important research opportunities related to the molecular basis of complex phenotypes remain unexploited by the ant research community.