When we collect an organism from the deep ocean, the easiest thing to document is its morphology: the shape of its body and its anatomical features. However, we can actually learn even more by sequencing its genes. With genetic information, we can learn what it eats, how it makes bioluminescent light, who are its closest relatives, and how it is adapted to survive in its unique habitat.

We use three approaches to gene sequencing: single specific genes, whole genomes, and transcriptomes. The genome includes all of the instructions for things that the organism knows how to make, as well as genetic material which controls when those genes are used. The transcriptome is a snapshot of which genes are in-use at a particular time in an organisms life. These are useful because the gene sequence has been “cleaned up” before we sequence it, so you usually know exactly what protein will be made. And single genes are used when we know we want to compare a particular sequence —say a bioluminescent protein or genetic fingerprint — to equivalent genes from other species.

Recently we have focused on chromosome-scale genomes from ctenophores (comb jellies), meaning that when we’re done all the DNA can be put together in the same way that it is organized within the organisms cells, and not fragmented into smaller bits.

We have developed methods to sequence single fingerprinting genes from the full diversity of ctenophores, and are applying them to get a true measure of diversity and species ranges.

We are using transcriptomes to study the origins of bioluminescence and to look at how different proteins in ctenophores are tailored to function at high pressure.