Differences in the suitability of published honey bee (Apis mellifera) reference genes between the African subspecies Apis mellifera scutellata and European derived Apis mellifera

Abstract

Quantitative real-time polymerase chain reaction (qPCR) is a method widely used to determine changes and differences in gene expression. As target gene expression is most often quantified relative to the expression of reference genes, the validation of suitable reference genes is of critical importance. In practice, however, such validation might not be thoroughly conducted if the same species and the same tissue or body parts are used for qPCR experiments. Here we show, that qPCR reference genes published for workers of European honey bee (Apis mellifera) subspecies fail to be stably expressed in workers of the African subspecies Apis mellifera scutellata. This is the case even when the sampled workers are in the same life stage, the same organ was dissected and the same reagents were used. Thus, reference genes need to be thoroughly re-tested before they can be used as suitable references even when the only thing that changes is the subspecies used.