Researching the link between genotype and phenotype

Professor Peter Dearden, from the University of Otago, is interested in how genotype makes phenotype. In this video, he talks about his laboratory’s research where they manipulate individual genes and observe any resulting changes in phenotype.

Jargon alert

• Genotype: The genetic information, or DNA sequence, of an individual organism

• Phenotype: The observable physical or biochemical characteristics of an organism, determined by both genetic makeup and environmental influences.

Transcript

Professor Peter Dearden

So genotype is the sort of sum of the genes – the genome of an organism – and phenotype is the shape and the morphology or the physiology of an organism, and my real interest is how you go from one to another.

So how does genotype make phenotype? And I think that is probably the most important question in biology at the moment. As a geneticist, we spend a lot of time killing a gene and saying what, how does that change the phenotype? So we look at phenotypes but we are really studying the genotype through the phenotype. Sounds very complicated but it’s really that these things map to each other, and we need to understand how you get the phenotype from the genotype to understand how organisms really work. Because we want to do things that’s more than just describing differences. We want to actually show that this difference has occurred and the importance of it. To do that, we have to mess with genes.

So genetics, the field is very powerful because what it does is it says OK, what happens to the development of the organism if we turn off that gene there or that gene there or both of those genes together? We have now discovered a way to turn genes off in a bee embryo or in an aphid embryo or any other sort of embryo, and now we’ve got this exciting research to go ahead with. We can actually take out individual genes and say what happens when we take this gene out, and what does that tell us about how the role of that gene has changed? So it’s very exciting at the moment because we have broken through some of those challenges.

But it’s always hard, you are never working… none of the work we do seems to be easy. There is always a problem, there’s always a technical problem, but once you’ve got through those technical problems, the results are fantastic.