I forgot to say my second post is about bees. Yes … this blog now has a bee-line. In future, I’ll post some news from the hives, but in this one I am drawing a huge arc from a wonder of nature to the making of babies in Petri dishes.
Among so many wonders in the apiary, the queen is a creature of singular awe. When you watch her surrounded by castes of worker and guard bees she might remind you of an absolute ruler, like Good Queen Bess (Elizabeth I of England), commanding armies, navies, and the allegiance of a retinue of courtiers.
But, in fact, she serves the colony as an egg machine and then, of course, she can’t be a Virgin Queen. When you carry out a hive inspection (angry guards buzzing your head) you may see her crawling over the honeycomb, depositing an egg the size of a grain of rice here and there in an empty cell. That’s all she ever does.
This brings me to bee sex… The queen has an identical genetic makeup to workers (male drones that fertilize her in nuptial flight have only half their chromosomes). So what makes the difference between her and the smaller, sterile workers?
For a start, there is no matrilineal inheritance of the ‘crown’ in hives. It is the workers, not a reigning monarch, who decides which cell will be the nursery of her successor. It is a mystery how they choose the cell of destiny, like the search for the next generation of the Dalai Lama, but their wisdom seems to me more dependable than the throw of a genetic dice for inheriting the crowned headship of a European state, which sometimes produces a good number, sometimes bad.
What makes the difference between a larva growing up in a cell as a queen instead of a worker is a continuous diet of Royal Jelly fed by nursery workers. A Japanese researcher recently showed that it comes down to a single type of protein, called royalactin: the rest of the jelly is a mixture of familiar vitamins and minerals.
Royal Jelly is scooped out of queen cells commercially for true believers in its powers to improve fertility and prolong healthy life. Some of the current Queen Elizabeth’s grand-children are jelly babies, since their mothers are reputed to have eaten the stuff before and/ or during pregnancy. I guess the story has done more for sales than health, brains, or longevity, but I don’t want to wade into the muddy waters of dietary supplements right now.
The bee larva fed continuously on Royal Jelly undergoes an amazing transformation. She grows larger, behaves differently, develops functional ovaries, and lives ten-times longer than other bees. How does royalactin work? By epigenetics.
This new research field promises to fill a lot of gaping holes in our knowledge about health, fertility, and disease. In a way, epigenetics is about switches in the DNA molecules that encode our genes. The famous double helix molecule is not naked; it is tagged and bundled with proteins that affect whether neighboring genes are switched on/ off.
When researchers in Heidelberg, Germany, compared tags (called methyl groups) between queens and workers they found differences in over 500 genes, all of which are attributed to the diet. I imagine royalctin plugging into a special groove in the DNA bundle where it turns on queen genes and switches workers’ genes off. Just as the actions of insect hormones and pheromones are often specific to the type of animal, neither should we expect royalctin to affect us.
Now, back to babies conceived in Petri dishes, which I wrote about last time. Every parent wants the best for their child. We heard that one patient, hoping to improve the chances, asked the IVF lab staff to place magnets under the dishes of her embryos, and another requested transferring the embryo to her uterus according to an astrological calendar. We never heard of anyone wanting Royal Jelly in the culture fluid, but I expect the request was made somewhere (and denied). But I’m not ending on a whacky note. Some scientists have warned that IVF babies might be at a slightly higher risk of physical abnormalities caused by epigenetic programs going awry, but the evidence is far from clear. The overwhelming story about IVF safety is reassuring, and Lucinda, in whose laboratories about 15,000 babies were conceived, agrees that had our children been conceived in a Petri dish we would not be more anxious than when it happened naturally.
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