Transgenerational accumulation of methylome changes discovered in
commercially reared honey bee (Apis mellifera) queens
Whether a female honey bee (Apis mellifera) develops into a worker or a
queen depends on her nutrition during development, which changes the
epigenome to alter the developmental trajectory. Beekeepers typically
exploit this developmental plasticity to produce queen bees by
transplanting worker larvae into queen cells to be reared as queens,
thus redirecting a worker developmental pathway to a queen developmental
pathway. We studied the consequences of this manipulation for the queen
phenotype and methylome over four generations. Queens reared from worker
larvae consistently had fewer ovarioles than queens reared from eggs.
Over four generations the methylomes of lines of queens reared from eggs
and worker larvae diverged, accumulating increasing differences in exons
of genes related to caste differentiation, growth and immunity. We
discuss the consequences of these cryptic changes to the honey bee
epigenome for the health and viability of honey bee stocks.