[Phoebee]

This has probably been asked and answered a hundred times, but I could not find it in a forum search, and none of my books answer this specific question.

I know queens and workers are diploid, and drones are haploid. Essentially, drones are sperm with wings.

The queen's eggs are also haploid, until fertilized, which produces diploid eggs that produce workers or queens. If unfertilized they produce haploid drones.

The queen is diploid, so could in principle contribute either a maternal or paternal chromosomes to her eggs. Or a mix. I know how this works in mammals. For humans you have 23 chromosome pairs. The creation of sperm and eggs splits each pair, contributing one at random to the haploid reproductive cell, allowing a tremendous amount of variation in offspring. But is it this random in bees? Do bee eggs favor the maternal contribution?

 

[sqkcrk]

Favor? Dominant traits are still dominant traits. Consider that it seems as though an AHB queen that mates w/ nonAHB drones exhibits AHB characteristics and​ that a nonAHB queen that mates w/ AHB drones exhibits AHB characteristics too.

 

[Phoebee]

You caught me while reading this:

http://www.glenn-apiaries.com/principles.html

My question comes because my teensie little apiary has only two hives, and I'm about 3 miles and one mountain gap from the nearest other hives that I know of. But they're recently-built nucs, and if I'm doing the bee math right, most of the drones presently flying are still the offspring of the colonies from which the nucs were built. In other words, it could well be I've got a lot of drones of mixed West Virginia ancestry, born on out on the almond groves, plus a few recent additions from the introduced queens.

If, in fact, each drone is a random mix of the 16 chromosomes of his mom, and I've still got four moms in the mix, then there is pretty good diversity present from such a small apiary.

One of my queens evidently quit laying recently and the hive created a handful of supercedure cells. I'm planning to let them go ahead and raise a queen. Plus a friend is offering me a nuc that is supposed to have VSH ancestry. So maybe I'm not as bad off as I though considering the apiary size.

Eventually my drones should find the hives out past the mountain gap, and they will find mine, and maybe there will be drone yards that open up the opportunity for any queens I raise. So hopefully there are more genes around than I originally thought, possibly with some local selection pressure already applied.

None of them should be africanized. In fact, so far they're the gentlest little sweethearts you could ask to keep.

 

[sqkcrk]

There are a lot more bees out there than anyone knows about. You'd have to be really secluded before you would end up w/ unmated queens or poorly mated queens.

 

[JSL]

You are correct. There is a great deal of genetic diversity in your four colonies. Honey bees have one of the highest recombination rates, and as Mark pointed out, there are a lot of colonies out there, even if you can't see them.

 

[Kamon A. Reynolds]

Shoot I know a guy who raise 2000 plus queens a year and doesn't have drone colonies at all. I feel this is negligence on his part. Yes there are alot of other bees around but I would hope that all producers/sellers would have drones of exceptional qualities to insure not only the best mated queens but also the toughest genetically.

Unless I was trying to mate 50-100 at a time on a consistent basis I wouldn't bother.

 

[Juhani Lunden]

Do bee eggs favor the maternal contribution?

This would be an interesting point to study. I would like to know more of that myself. I once read (did not copy the text to my files!) about the "fight" of genes, the idea of that being that a gene wants its own replicas to the offpring. Sounds scifi, doesn´t it?

Human dna genealogy is my hobby. In these results it is interesting to notice that female persons have about 20-30% of their dna cousins having similarities in mitochondrial dna(this is coming from mother, in the egg cell, both to girl and boy babies), the tested males have around 5% of their dna cousins having similarities in mitochondrial dna. Females have more dna cousins coming from mothers side than males.

 

[Phoebee]

Sounds scifi, doesn´t it?

Heh, I WRITE science fiction. No kiddin'. But with biology, I guarantee you that nature has more imagination than all the members of the Science Fiction Writers of America put together.

 

[Juhani Lunden]

My e-mail is [email protected]

 

[Phoebee]

 

[Juhani Lunden]

All the experts in genetics on the forum, where are you? Here is a question to show off.

Do bee eggs favor the maternal contribution?

 

[sqkcrk]

Juhani, let me show my ignorance. A queen comes from a fertilized egg. So she is the result of her Mother and her Father. Are you asking whether her Father's contribution is passed on in her eggs? Or if just her Mother's contribution/genes?

Dangerously thinking out loud here at 5AM. The unfertilized egg will produce a drone. The sperm came from a drone. When used to fertilize an egg (a drone in its most basic form in essence) queens or workers are produced. They're all drones. Just that some are twice the drones that drones are.

Where is the mitocondrial DNA in a honeybee? In the drones?

 

[Juhani Lunden]

If there is some favoring it happens when egg is produced. Queen is diploid, and she uses all her genes to produce the eggs. Of course there is mothers and fathers contribution in the eggs, but are there more genes from mothers side? This would be an advantage, if some genes affect for instance egglaying capacity and it comes from her mother.

Mitochondrial dna is in the egg cell and by cell divisions it goes to all cells of all creatures.

 

[deknow]

I don't believe there is any bias towards contributuon...except for the ironic twist that all male traits come from the mother with no paternal contribution.

 

[JSL]

Greg Hunt and others have been working on this concept. They may have a more recent publication of their findings, but below is a short abstract from a thesis out of Greg Hunt's lab. The work suggests a slight bias for certain genes from the male or female.

http://gradworks.umi.com/35/56/3556196.html
Characterizing the honey bee genome for parent-of-origin effects on gene expression
by Emore, Christine Michelle, Ph.D., PURDUE UNIVERSITY, 2012, 126 pages; 3556196

Abstract: Genomic imprinting has been studied extensively in higher plants and mammals where it plays a crucial role in development and has been linked to cancer and other diseases in mammals. The honey bee is one of the few invertebrate species in which genomic imprinting has been studied and could give new insights into parent-of-origin effects on behavior. The hypothesis tested was that parent-of-origin effects do exist in the honey bee and was done by using RNA-seq on two life stages of reciprocal crossed honey bees. Two different RNA-seq systems were used. The project was first done using the SOLiD 4 system, but validation of the results was poor due to a large number of false positives created from systematic and alignment biases that were not taken into account by the statistical methods used. The second system was the Illumina HiSeq 2 and the study was done using replicates and generalized linear mixed model statistics that could model and correct for systematic biases introduced during sequencing and alignment. The Illumina study showed that parent-of-origin effects do take place in the honey bee and the results were validated by sequencing PCR products of parent-of-origin effect transcripts using the Illumina MiSeq. The Illumina study showed that parent-of-origin effects are more evident in adult honey bees than in early larval stages, contrary to mammals and plants where the majority genomic imprinting takes place in early development. Regardless of life stage parent-of-origin effects in the honey bee are primarily biased towards maternal expression with the strongest maternal expression found in nuclear copies of mitochondrial genes or numts. The numts are not complete genes but gene fragments or pseudo-genes that are actively transcribed by the nuclear genome, which suggests a biological function and evolutionary selection for conserved maternal expression.

 

[Juhani Lunden]

Greg Hunt and others have been working on this concept.
...Genomic imprinting has been...

I´m not sure imprinting is what Phoebee meant, I sure didn´t. I meant the formation of an egg, and the genes which come in it.

 

[Richard Cryberg]

All the experts in genetics on the forum, where are you? Here is a question to show off.

Do bee eggs favor the maternal contribution?

All critters have two kinds of DNA, nuclear and mitochondrial. Mitochondrial DNA is passed intact from mom to offspring with Dad seldom making any contribution at all. This DNA is not in the nucleus and does little besides run the energy chemistry in mitochondria.

Nuclear DNA is totally scrambled by crossovers before egg formation happens. So, by the time crossovers are done there are no maternal or paternal chromosomes left. There can be individual genes or DNA regions that carry epigenetic marks that define them as being maternal or paternal. And, it is always possible such marks can influence if the marked DNA region goes to the egg or to a polar body. In genetics it is a good bet if you can think up a scheme mom nature will already be using it someplace.

In drones there is no crossover process so chromosomes in haploid sperm are just like they are in the haploid drone.

 

[Juhani Lunden]

And, it is always possible such marks can influence if the marked DNA region goes to the egg or to a polar body. In genetics it is a good bet if you can think up a scheme mom nature will already be using it someplace.

Any studies, publications?

 

[Michael Bush]

> But is it this random in bees?

Yes.

>Do bee eggs favor the maternal contribution?

That depends on what you mean by this sentence. The haploid egg produced by the queen is a random single set built from pairs (diploid). Those are just random but they are both maternal contributions to the egg. The other half of the worker or queen produced from an egg is the single set (haploid) that comes from the drone's sperm. Since the population of bees in the hive has half of their genetics from the queen (always the same queen except in rare circumstances) and the other half from a multitude of drones, the maternal contribution (as in "the current queen's contribution) is higher than any given drone.

So if by "maternal contribution" you mean what the queen who is laying the egg contributes, all the genes that go into the haploid egg come from here. How can there be any favor? If you mean the queen's mother's contribution to that egg getting any preference, no it does not.

 

[JSL]

Juhani,

Imprinting as used in genetic research is not the same as imprinting in the case of young geese "imprinting" on their parents. It refers to the genetic influence imparted by the male or female, in this case bees. This is over my head, but appears to be the first described instance in honey bees where it is not the traditional 50% from mom and 50% from dad at least in terms of expression. I think Hunt did this work in the expression of behavior.