Dr Clémence Fraslin on genomic selection in aquaculture

She talks about the importance of better understanding the genetics of disease resistance in aquaculture, as this will help breed more resistant animals and thus reduce the use of drugs to treat them; the challenge of adapting technologies to make advances affordable for most breeders worldwide; and the importance of a supportive work environment and mentor to promote work-life balance.

During her PhD at the Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE, Jouy-en-Josas, France), Clémence worked closely with French trout farmers to better understand the genetic architecture of the response of rainbow trout to infection by a bacterium. In her first postdoc with the same INRAE team, she studied the genetics of spontaneous maleness in female rainbow trout, gaining insight into the complicated sex determination in fish species. For her second postdoc, she moved to the Roslin Institute to expand her expertise in genomic selection to improve disease resistance in rainbow trout. She worked closely with the Finnish National Breeding Programme, led by Luonnonvarakeskus (Luke) University.

Today, she is a core scientist at the Roslin Institute in Diego Robledo's group in the Aquaculture team and is working on several projects, mainly studying the genetic architecture of disease resistance in fish and implementing cost-effective genomic selection in different fish species.

Could you briefly summarise your work?

I am a quantitative geneticist in the field of aquaculture. So far, my work has focused on disease resistance in salmonids (salmon and trout), but I have also done a postdoctoral project on sex determinism in rainbow trout. In my work, I am trying to better understand the genetic basis of resistance to major pathogens in fish species and to look for genes that explain why certain fish are resistant and others are susceptible. In most cases, we have found that disease resistance is heritable and can be passed from parents to offspring, but that it is subject to complex genetic control involving a very large number of genes distributed throughout the genome. I also work with breeders to help them implement genomic selection to select the best fish to improve a particular trait of interest for them. Using phenotypic records, genomic models, and markers on the genome, we can predict whether a fish is likely to be more resistant to a disease than another fish, and therefore which fish should be selected to pass on its resistance to offspring as the parent of the future generation.

Why is your research important? How is it relevant to people's lives?

Demand for fish and aquatic species for human consumption is increasing, but we have reached the limits of sustainable fisheries. Aquaculture can help meet demand through the production of farmed fish, and selective breeding is a key element of sustainable farming because it can help produce more fish that are more resistant to disease, that use resources more efficiently, or that are better adapted to challenging environmental conditions. A better understanding of the genetic basis of disease resistance is important because it helps breed more resistant animals and thus reduce the use of drugs to treat them. In aquaculture, this is of great importance because vaccines and other solutions are often limited and diseases are expected to become even more important with global warming.

What are the major challenges in your field?

I think one of the biggest challenges is to adapt technologies to make progress affordable for all. So far, genotyping is still very expensive, and since we work with large numbers of individuals in aquaculture, it is still prohibitively expensive for most breeders worldwide. Another challenge that makes aquaculture research so exciting is the fact that we work with a large number of species, all of which are very different. Some of them are well known and researched, such as Atlantic salmon, while most farmed species are new and have very little genetic information, such as seaweeds. New species with complex genomes always present us with new challenges, and that keeps us entertained.

What inspired you to be a scientist?

I was always very curious, always asking questions and experimenting. My parents bought me books, always tried to answer my questions, and never turned me away (that must have been exhausting). I was lucky to have some amazing teachers and people around me who were not annoyed by my constant curiosity, and I was always (and still am) excited to learn more. When I was a teenager, I wanted to get a PhD in chemistry and become a lecturer. That was before I realised I hated chemistry... Nevertheless, I got the PhD part right!

What do you like best about your job? What do you like the least?

I like the flexibility of our work and the variety of things we do (from analysis to writing papers and communicating our findings). I am always really happy to analyse new data sets and figure out what went wrong. I am a very social and talkative person, so I love communicating about science and going to conferences to meet other researchers. Aquaculture genetics is a small community, and it's nice to meet people again that I have worked with on previous projects.

I do not like the impermanence of the work; it's really hard to get a permanent research position, and the fixed-term contracts during the long postdoc years are nerve-wracking. I also do not like the pressure of producing publications, publishing before others, and more. I feel like I am always in a rush of "I should be writing" moments, and I would enjoy having more time to do research and build collaborations instead of competition.

If you could have tea with another scientist (alive or dead), who would it be? What would you talk about?

I would like to have tea with Hertha Ayrton. She was an electrical engineer, mathematician, physicist, inventor (she published 26 patents!), and a strong advocate for women's rights as a suffragette. Since she was a good friend of Marie Curie, perhaps we can have a tea party? In that case, I'd love to invite Nettie Stevens, Rosalind Franklin, and Barbara McClintock to join us so we could talk about genetics, DNA, and sex determinism (highly complex in fish and super interesting) with three pioneering women in genetics. Nettie Stevens discovered the existence of sex chromosomes through her work with insects and was the first to prove the existence of XX and XY chromosomes. She never received the recognition she deserved. Rosalind Franklin is famous for discovering the double helix structure of DNA. Both deserved the Nobel Prize for their discoveries, but it was awarded to men who were their colleagues or superiors. McClintock proved the principle of genetic recombination during meiosis and transposable elements by studying coloured corn. Initially, her discovery was not well received by the public, but 30 years later she was awarded the Nobel Prize in Physiology and Medicine - the first woman to receive this Nobel Prize undivided! We would also talk about women in science, both famous and forgotten, and how difficult it can still be today to do research as a woman in a male-dominated environment.

What is the most unusual thing you have done as a scientist?

It has nothing to do with aquaculture, but during an internship in New Zealand, I had to collect urine and faeces samples from dairy cows and then grind up the dried excrement for chemical analysis. Dried cow poop is... very volatile. On the "Fun Fact" side, I visited a crocodile farm in Australia and learned that you can make ice from crocodile eggs (not sure if I would be brave enough to try it!).

If you weren’t a scientist, what would you be doing?

I love having plants in my home and taking care of them, so I would probably work in a plant shop to have as many plants as possible.

Do you have any advice for people who want to go into this field of research or start a career as a scientist?

Always be curious and excited about your work, be bold, ask questions, and talk to people (even the scary-ultra-famous professor) to build a network. Finally, a supportive environment and a supervisor who is a good mentor and pays attention to work-life balance are very important during (and after) your PhD.

What do you think are the major challenges facing humanity? How can science help?

I think global warming is the biggest challenge we all face, and we have to do something about it if we want to continue to live on our planet. Scientists have a critical role to play in finding alternative ways to produce greener energy and more sustainable food that will feed us all while dramatically reducing our impact on the planet. Science has done its work to demonstrate the importance of global warming and it has already found solutions, now politicians and policy makers need to listen to science and act.