Deformed wing virus (DWV) in association with Varroa destructor is currently attributed to being responsible for colony collapse in the western honey bee (Apis mellifera). The appearance of deformed individuals within an infested colony has long been associated with colony losses. However, it is unknown why only a fraction of DWV positive bees develop deformed wings. This study concerns two small studies comparing deformed and non-deformed bees. In Brazil, asymptomatic bees (no wing deformity) that had been parasitised by Varroa as pupae had higher DWV loads than non-parasitised bees. However, we found no greater bilateral asymmetry in wing morphology due to DWV titres or parasitisation. As expected, using RT-qPCR, deformed bees were found to contain the highest viral loads. In a separate study, next generation sequencing (NGS) was applied to compare the entire DWV genomes from paired symptomatic and asymptomatic bees from three colonies on two different Hawaiian islands. This revealed no consistent differences between DWV genomes from deformed or asymptomatic bees, with the greatest variation seen between locations, not phenotypes. All samples, except one, were dominated by DWV type A. This small-scale study suggests that there is no unique genetic variant associated with wing deformity; but that many DWV variants have the potential to cause deformity.
Bibliographical noteFunding Information:
This work was part funded (Laura E. Brettell, Stephen J. Martin and Jessica R. da Silva) by ?Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)? via Special Visiting Researcher?PVE between Stephen J. Martin and Carlos A. L. de Carvalho (number 400425/2014-9). The Brazilian honey bees were collected under Sistema de Autoriza??o e Infora??o emBiodiversidade (SISBIO) license number 46906-1. Laura E. Brettell was also funded by a Santander International Travel Bursary for the Brazil fieldwork, and from the British Beekeeping Association and a Salford University PtE studentship for the Brazilian laboratory work. We thank the C. B. Dennis British Beekeepers? Research Trust for funding this research. Stephen J. Martin and Laura E. Brettell were funded by a CB-Dennis program and Apis_m for the Hawaiian honeybee field and laboratory work. Gideon J. Mordecai is funded by the British Beekeepers Association and the University of Reading. Declan C. Schroeder is funded by The Marine Biological Association Senior Research Fellowship. Ian M. Jones is funded by the UK Biotechnology and Biological Sciences Research Council.
- Deformed wing virus
- Next generation sequencing