A global researcher team, led by the Experimental Ecology Group of the technical University in Zurich, Switzerland (Eidgenössische Technische Hochschule) has decoded the genome of two commercially significant bumble bee species: the European Bombus terrestris and the American Bombus impatiens.
The genomes of the two species are very similar and contain about 20,000 different genes on 18 chromosomes. Analyzing the genes, Ben Sadd, Seth Barribeau and 80 researchers from all over the world, focused on the immune system and found that only about 150 genes play a role in the immune response of the two bumble bee species – a result they share with the honey bee whose number of immune genes is just as low. The immune repertoire of flies and mosquitos, on the other hand, is about twice as large.
The results suggest why bumble bees – and honeybees for that matter – are having problems in today’s environment: Compared to flies or mosquitos, their immune system is underdeveloped, which means their defenses against bacteria and fungi are low. But it is not only their weak immune system that makes their lives difficult. The researchers also found that bumble bees – just like honey bees – own very few genes to regulate detoxification. This suggests that they are particularly susceptible to pollutants.
These findings offer the basis for further research into helping pollinators to cope with stress factors.
Bumblebees are natively found around the globe, except for sub-Saharan Africa and Oceania. Their commercial value has increased with the recent losses in managed honey bee populations. B. terrestris and B. impatiens are both reared commercially and distributed internationally.
A summary of the study (in German) was published in the scientific news portal “Informationsdienst Wissenschaft”:
You will find the full study report (in English) in the online magazine “Genome Biology”: