EASTBIO: Using gene drives to control sea lice in Atlantic salmon aquaculture at the Universtity of Edinburgh

Supervisors:  Professor Ross Houston, Professor James Bron, Dr Diego Robledo, Dr Sean Monaghan.

In Atlantic salmon farming, ectoparasitic copepods, commonly known as sea lice, are the primary disease threat to sustainable production, costing more than £700 million worldwide. Frequent treatments can be required which can be environmentally damaging and have negative impact on fish welfare. Therefore, novel control and prevention strategies are urgently needed.

A number of programs for control of pests and parasites worldwide have involved the release of high numbers of sterile individuals, e.g. screwworm flies, which can reduce the overall fecundity of target populations. However, such programs need to generate high numbers of eggs / animals, which is not considered feasible in a sea lice / salmon model.

As an alternative approach, synthetic gene drives can control sexually reproducing pests and parasites, based on positively-biased inheritance of deleterious genes to alter entire populations. Gene drives ensure the preferential transmission of particular alleles, by cutting chromosomes that do not encode the drive at a specific site and inducing the cell to repair the damage by copying the drive sequence onto the damaged chromosome. The result is that almost all the gametes produced from heterozygous individuals will contain the allele with the gene drive (termed super-Mendelian inheritance).

Gene drives combined with genome editing can theoretically facilitate the generation and spread of any given mutant allele throughout a population. A high profile example is the use of a Crispr-Cas9 gene drive system to create and spread a recessive female sterility phenotype in the malaria mosquito Anopheles gambiae (Hammond et al. 2016, Nature Biotechnology). The proposed CASE studentship project will investigate the potential of similar gene drives to control sea lice populations and in particular to target reproductive fitness of the parasite.

Successful candidates will have the opportunity to work within internationally recognised teams at Roslin Institute, University of Edinburgh and Institute of Aquaculture, University of Stirling and to receive training in cutting-edge molecular and parasitological techniques. Both research groups focus on applied aspects of aquatic biology having direct applications in the UK and global aquaculture industry. This is further bolstered by the support of the Scottish Aquaculture Innovation Centre as a CASE studentship.

Potential students should hold a good UK bachelor’s degree (first or upper second-class honours degree), an MSc degree or equivalent international qualifications in a genetics / molecular biology / parasitology related subject area.

Informal enquiries can be directed to Professor Ross Houston at [email protected]

This 4 year PhD project is part of a competition funded by EASTBIO BBSRC Doctoral Training Partnership (DTP) http://www.eastscotbiodtp.ac.uk/how-apply-0 .

EASTBIO Application and Reference Forms can be downloaded via   http://www.eastscotbiodtp.ac.uk/how-apply-0

Please send your completed EASTBIO Application Form along with a copy of your academic transcripts to [email protected]

You should also ensure that two references have been send to [email protected]  by the deadline using the EASTBIO Reference Form.

This opportunity is open to UK and international students and provides funding covering stipend and UK level tuition fees.  The University of Edinburgh covers the difference between home and international fees meaning that the EASTBIO DTP offers fully-funded studentships to all appointees.  There is a cap on the number of international students the DTP recruits.  It is therefore important for us to know from the outset which fees status category applicants will fall under when applying to our university.

Please refer to UKRI websiteand Annex B of the UKRI Training Grant Terms and Conditionsfor full eligibility criteria.

Closing Date: 16th December 2021