The Nuanced Evolutionary Consequences of Duplicated Genes

Even before experimental biologists had characterised the molecular architecture of
genes, gene duplication had already been proposed as an important driver for organismal evolution.
Early proponents of Darwinian natural selection knew that traits were passed down through
generations via a set of instructions, but it was subsequently appreciated that the possibility of
making changes to this hereditary material would become increasingly limited as organisms became
adapted to their environment over time. In this way, natural selection was considered first and
foremost to be inherently conservative. Freeing the potential for adaptation from the shackles of
conservation is to be thought to be gene duplication. A gene duplication is the complete or partial
copying of a DNA sequence on a chromosome, after which each gene evolves separately to form
paralogues. However, it is still not known how gene duplications catalyse multifaceted evolutionary
processes such as speciation, especially in light of how many paralogous genes maintain redundancy
with one another over long evolutionary timescales. Thus, in order to appreciate the role of gene
duplications in complex evolutionary events, it is important to first understand the relationships
between paralogous genes using robust molecular genetic techniques. My work thus far in
characterising the redundancy relationships between members of a large developmental gene family
in the nematode, Caenorhabditis elegans, has shown that the fates of duplicated genes are more
nuanced than previously proposed, often exhibiting complex and unexpected redundancy
relationships due to surprising patterns of specialisation. Building on the insights gained from this
work, I hope to continue to illuminate gene duplication dynamics and their impact on organismal
evolution.