Research into amitraz resistance continues at dnature
2025-05-08
John Mackay, Technical Director
It is interesting that once a genetic culprit can be linked to treatment resistance, that reports of resistance increase in the literature. The genetic target of amitraz was only reported a few years ago but since then mutations linked to resistance continue to be reported. All in the same gene but unlike pyrethroid resistance (the major mutation being the single L925 amino acid), these mutations are all along the receptor gene in the DNA regions that span across cell membranes.
The latest mutation has been reported in Korea, with a mutation called T115N (amino acid threonine (T) changes to asparagine (N) at position 115). As the Korean authors write “To manage amitraz resistance effectively, it is critical to monitor novel resistance-associated mutations continuously” – and here at dnature, we’re working on a new test for this mutation. That will make 5 mutations that have been reported to be associated with amitraz resistance so we’re also looking if we can develop a single screening test as well for these membrane-associated regions.
It should be pointed out that none of the other mutations have been reported to date and there is nothing to suggest that amitraz-based treatments are not working as intended in New Zealand colonies. Phil Lester’s group at University of Victoria have also shown that amitraz remains effective in killing varroa.
Rapid spread of Amitraz resistance linked to a unique T115N mutation in the octopamine receptor of Varroa mites in Korea. https://doi.org/10.1016/j.pestbp.2025.106387
