Peptide biomarkers used for the selective breeding of a complex polygenic trait in honey bees

Abstract

We present a novel way to select for highly polygenic traits. For millennia, humans have used observable phenotypes to selectively breed stronger or more productive livestock and crops. Selection on genotype, using single-nucleotide polymorphisms (SNPs) and genome profiling, is also now applied broadly in livestock breeding programs; however, selection on protein/peptide or mRNA expression markers has not yet been proven useful. Here we demonstrate the utility of protein markers to select for disease-resistant hygienic behavior in the European honey bee (Apis mellifera L.). Robust, mechanistically-linked protein expression markers, by integrating cis- and trans- effects from many genomic loci, may overcome limitations of genomic markers to allow for selection. After three generations of selection, the resulting marker-selected stock outperformed an unselected benchmark stock in terms of hygienic behavior, and had improved survival when challenged with a bacterial disease or a parasitic mite, similar to bees selected using a phenotype–based assessment for this trait. This is the first demonstration of the efficacy of protein markers for industrial selective breeding in any agricultural species, plant or animal.

Hygienic behaviour in honeybees: a comparison of two recording methods and estimation of genetic parameters

“…Table III shows the estimates for the variance components and the resulting heritabilities and repeatability of HB recorded with FKB*. As expected, heritability for the average HB score of two records (0.37 ± 0.25) was higher than the one estimated with the repeatability model (0.23 ± 0.16), but it is smaller compared to the value of 0.65 ± 0.61 reported by Harbo and Harris (1999) and to the values of 0.56 and 0.57 recently published by Guarna et al (2017). The higher heritability is explained by the fact that in the average model, the dependent variable was the average of two HB measures.…”

Multiple quantitative trait loci contribute tolerance to bacterial canker incited byPseudomonas syringaepv.actinidiaein kiwifruit (Actinidia chinensis)

“…Acc03527.1 ( AGAMOUS-like ) is located very close to the QTL on LG3 in P1 for Psa_score_Field and an ammonium transporter gene has been recently shown to be involved in stem rust resistance in wheat 77 . Our study therefore provide new resource for candidate RNA-biomarkers for predicting tolerance in kiwifruit field breeding nurseries that can lead to improve the speed of selective breeding of multi-genic trait 78 .…”

A death pheromone, oleic acid, triggers hygienic behavior in honey bees (Apis mellifera L.)

“…We kept honey bee colonies at four separate apiaries in Greater Vancouver, Canada, and performed hygienic testing as previously described (22). All hygienic testing, sampling and odor assays were completed during the summer of 2017.…”

“…This is an effective defense against major brood diseases, including chalkbrood (Ascosphaera apis) (17,18), American foulbrood (Paenibacillus larvae) (13,19), and the devastating varroa mite (Varroa destructor) (19)(20)(21). When highly hygienic colonies are inoculated with these pests or pathogens, they are less likely to develop clinical symptoms than non-hygienic hives (19,22,23).…”

“…Hygienic honey bees have superior olfactory sensitivity compared to non-hygienic honey bees (24,27), which likely depends in part on differences in antennal gene expression (22,(28)(29)(30)(31)(32). In a search for antennal biomarkers for hygienic behavior, we previously identified two odorant binding proteins -OBP16 and OBP18 -that significantly correlated with colony hygienic score (31).…”