What is a gene for?

The word “gene” means different things to different people, and can even be used in multiple ways by the same individual. In this review, I follow a particular thread running through Griffith and Stotz’s “Genetics and Philosophy: an introduction”, which is the way that methods of investigation influence the way we define the concept of “gene”, from nineteen century breeding experiments to twenty-first century big data bioinformatics. These different views lead to a set of gene concepts, which only partially overlap each other, each of which picks up on a different part of gene behaviour, function or scientific utility. This plurality of concepts carries over to the use of the concept of “information” in biology, where the non-overlapping concepts can be connected to whether you view the genome as a blueprint for development, a response to environmental triggers, an engine of heritability, or a document of history.