Insect farming’s potential value to the future of food supply has been well documented. As ever, the challenge, says Eliaou Sellem, is scaling up from laboratory to industry.
Tenebrio molitor – or, as you may know it better, the Yellow Mealworm – is now a promising alternative to produce high-quality protein products with low environmental impact. However, to have a worldwide impact on feed and food alimentation, production must scale up at the industrialisation phase and deliver several kilotons of insect proteins per year.
This production objective implies an important concentration of individuals in the same place, leading to dealing with the genetic diversity and performance of the strains currently farmed. That's why Ÿnsect is leading a six-year R&D programme called ŸnFABRE, where the main objective is to develop all the required tools to propose a genomic selection scheme (reproduction, growth, food efficiency and disease resistance) adapted to our industrial farming conditions.
The first step, in collaboration with Thermo Fisher and CEA, is the development of a highdensity genotyping array. Prior to envisaging this tool, the tenebrio molitor genome of reference has been upgraded by combining Oxford Nanopore and Illumina Hi-C sequencing to construct a high-quality chromosome-scale assembly (Eleftheriou et al., 2022). Then a subset of 136 individuals, sex equilibrated, representing all the phenotypical diversity of Ynsect population, has been fully sequenced, aiming to underline the genomic diversity.
To have a worldwide impact on feed and food alimentation, production must scale up at the industrialisation phase and deliver several kilotons of insect proteins per year
From all these sequences, eight million SNPs (single nucleotide polymorphism) were highlighted. The genotyping HD array was made by choosing the most informative 679 205 SNPs, by covering the 49 first genome scaffolds (>90% of genome assembly) and 99.2% of coding regions.
Some 96 samples can be analysed at the same time, by hybridisations between the extracted and prepared DNA and the specific probes representing the different SNPs of interest. This tool is the cornerstone of the ŸnFABRE project, aiming to decipher the link between genomic information and phenotype performances. To do so, a population of reference – made by 4,000 phenotyped Tenebrio molitor generated through single pair mating and under pedigree – is currently genotyped with this array. GEBVs (genomic estimated breeding values) will be calculated through the array outputs, allowing the first establishment of an insect genomic selection scheme.
Outside the ŸnFABRE project, this tool can be used for several applications, such as the inbreeding level determination in a population or the identification of new traits of interest (larval survival, pupation, or emergence rate…). As tenebrio molitor is a scientific model species, this HD array represents a relevant advantage for academic purposes. Using this tool, Ÿnsect aims to develop the academic interest around the yellow mealworm.
- Eliaou Sellem is Genetics Project Manager at Ÿnsect
