Stefan Janusz reports :: March 2008

Thanks to the haplodiploid sex-selection mechanism of many species of bee, female worker bees are on average 3/4 genetically the same as their sisters. By contrast, human siblings share 1/4 of their genes. The curious thing is that the queen bee is, on average, as genetically similar to any of her sisters as any two sisters are to each other. So what causes her to snub the sisterhood and rise to regality?

The secret is royal jelly, a thick, milky substance made by workers in the hive's nursery from enzymes secreted by their throat glands mixed with honey. Larvae destined to become queens are fed it, while those destined to become workers are fed low-grade food. By using the technique of RNA interference (RNAi), researchers at the Australian National University in Canberra have created queen-like individuals by reducing the degree of DNA methylation on developmentally crucial genes. Methylation is one form of epigenetic imprinting with a dietary influence, and this work supports the idea that royal jelly reduces methylation. This work was published in Science.