# Mr. Drone...Whose your Daddy?



## beemandan (Dec 5, 2005)

Mosherd1 said:


> Since all the drones in a colony should be clones of each other (having no father only a mother).


Keep in mind a queen has two sets of chromosomes. One maternal and one paternal....so there will be two separate sets of 'clones' (an oversimplification as the characteristics of genetic material allow the occasional, random mixing of both).


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## deknow (Jul 17, 2006)

...not quite right.

think of a drone as "flying sperm". each drone has 1/2 the genetics from its mother...but each drone has a different half (think of a circle bisected by a line....as you change the angle of the line, you still get 1/2, but a different 1/2). In more conventional breeding situations (like humans) we don't produce only 2 kinds of eggs or 2 kinds of sperm....the same process is at work here.

However, each sperm that a particular drone produces is identical (and identical to the genetic makeup of the drone itself.

deknow


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## Mosherd1 (Apr 17, 2011)

Interesting, that makes more sense. I was hoping that there was something that I was missing. Seemed to easy/straightforward the way I was thinking about it.


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## Jim 134 (Dec 1, 2007)

Mosherd1 said:


> Originally Posted by Mosherd1
> 
> Since all the drones in a colony should be clones of each other (having no father only a mother).


But all drones have Grandfather but not the same one 



BEE HAPPY Jim 134


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## Grid (Jun 5, 2009)

The drones that gather in the Drone Congregation Areas (DCAs) come from up to 2 miles away, or so I have read. They come from any hives, kept or feral, in that range. If there are no other keepers in that area, and no (or very few) feral hives, it seems to me that the genetic diversity can't help but suffer, and in-breeding will be higher.

Anyone know of any studies showing the genetic diversity and % of inbreeding in a typical mated queen? Or in a queen from a situation that a human (like me) would consider to be low in genetic diversity? It would be nice if someone has demonstrated that even with a small number of kept hives in isolation that the ferals and other factors still managed to keep the diversity up.

Grid


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## jrbbees (Apr 4, 2010)

Mosherd1 said:


> Seemed to easy/straightforward the way I was thinking about it.


I don't think there is anything easy or straight forward about sex in any living thing.


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## David LaFerney (Jan 14, 2009)

deknow said:


> However, each sperm that a particular drone produces is identical (and identical to the genetic makeup of the drone itself.


I hadn't thought of that. Since each drones offspring has the exact same genetic contribution from that drone/father - really makes the drones more important than if they contributed varied sperm. For example if a drone has a gene for aggressive offspring then 1 out of 15 or so of the queens offspring will have that gene. Even if that is only a 50 percent chance of *those* bees being aggressive that's still a lot of foul tempered bees in a big hive.

That's a good reason to use drone foundation - so you can control the drone product of a hive that has undesirable traits.


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## NasalSponge (Jul 22, 2008)

While reading TIGTB I have learned there is a definite reason for laying workers....to flood an area with drones so to keep the queens genetics in play. I always thought is was simply the desperate move of a dying hive.


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## Mosherd1 (Apr 17, 2011)

What is TIGTB?


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## NasalSponge (Jul 22, 2008)

The Complete Idiot's Guide to Beekeeping.


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## Michael Bush (Aug 2, 2002)

It's always a bit confusing and there are a lot of misconceptions on the matter. So let's try to sort it out.

First, since the drones all don't have a father but do have a grandfather, how many grandfathers do they have? Answer: 1. The one sperm cell that united with the queens mother's egg is the one grandfather they have. How many genetic possibilities are there for a given drone from a given queen: Since the queen is diploid (has two sets of genes, one from her father and one from her mother) there is a 50 : 50 for each gene. So if you take the combinational analysis of each gene with two possibilities the number is very high, but for any given trait there are two and only two possibilites. 

Another misconception is that since they only have a mother that all the drones from that queen are identical. But they are not. They are a random set from that double set from the queen. For each gene they will get their one gene randomly from the two their mother has of that gene (the drones are haploid meaning the only get one set) which originated from either their grandfather or from their grandmother.


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## deknow (Jul 17, 2006)

errr, on the surface the 50/50 thing works, but since the genes are in specific locations of specific chromosomes, some traits are linked to one another (in cellular reproduction, it is the chromosomes that are replicated, not each gene separately). there are instances where genes jump from one chromosome to another (or aparantly, from one organism to another)....so these links are not 100%.

so, if you are looking at 1 trait, the 50/50 model holds. if you are looking at a number of traits, then there may be some linkage between them, and given one trait, there may be much more (or much less) of a 50/50 chance that another given trait will be present.

deknow


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## WLC (Feb 7, 2010)

Honeybees have the highest rate of genetic recombination known for invertebrates/higher eukaryotes.

As long as there's an average of 4 or 5 recombination events per chromosome pair every time a gamete is produced, asking the matrilineal vs patrilineal question for a specific trait becomes 'iffy' at best.

That high recombination rate is what makes Honeybees very useful for linkage map studies (think the statistics of recombination) and has allowed investigators like Spivak to map candidate genes for traits like hygienic behavior to specific chromosome locations.

deknow, the jumping gene issue doesn't lend itself readily to classical genetics. It's in the realm of molecular genetics.


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## deknow (Jul 17, 2006)

> deknow, the jumping gene issue doesn't lend itself readily to classical genetics. It's in the realm of molecular genetics.


??? I don't recall differentiating between the two. As this is your area of expertise, I'd be happy to hear any corrections or critique of what I write on the subject...but from your comment above, I can't tell if you are correcting the facts, or just pointing out that some of the factual information I posted falls under "molecular genetics". From a practical standpoint, does it matter?

deknow


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## WLC (Feb 7, 2010)

The high rate of genetic recombination in Honeybees by crossing over has been known for some time. Linkage maps of Honeybee chromosomes were available years before the sequencing of the Honeybee genome (2004) and the discovery of active retrotransposons by Maori in 2007.

High rates of crossing over in the chromosomes of Honeybees is normal. That's why you can't easily say if a trait is of patrilineal or matrilineal origin. The deck keeps getting shuffled on an individual chromosome level.

Jumping genes (retrotransposons) in Honeybees may very well insert themselves randomly according to Maori. That makes them unsuitable for the 'who's your daddy?' question.

My own research interest is for one specific type of retrotransposon, R2, that inserts itself in a conserved location in 28S rDNA.

The idea being, if I can identify an inserted sequence that can confer immunity via RNAi, then perhaps we can use drones and their sperm as a way of spreading these sequences.

That's why I'm interested in drone comb as of late and have been setting up an incubator. I'd like to test it out. 'Good, jumping genes' aren't much use if you can't find them.


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## deknow (Jul 17, 2006)

...the rate of genetic recombination might be high in honeybees, but this is hardly a new concept. I recall learning (and being tested on) genes jumping from one chromosome to another (and I believe from one loci to another...but I'm less sure about this) in high school biology in 1984.
We certainly know a lot more now than we did then...but if we are talking about genetics, I'm not sure why there should be (or why you pointed out) the difference between "classical" and "molecular" genetics. This may be a historically significant point, but our understanding (or our discussion here) has hardly been limited to "classical genetics".

deknow


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## WLC (Feb 7, 2010)

There is a difference between genetic recombination by 'crossing over' in chromosomes
and the insertion of foreign sequences by retrotransposition (think transgenics). One has been well characterized in Honeybees, and the other one is very new to Honeybee genetics and is 'uncharacterisitic'.

Regardless, the origin of specific traits beyond a single generation isn't very helpful unless you're doing linkage maps. There's too much reshuffling going on.


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## llang (Aug 13, 2010)

WLC, deknow, and Michael...

Great discussion... I know WLC will appreciate this clarification (my own background is Maize Molecular Genetics working on transposons/ later NeuroMolecular Biology). It is important to remember (there are exceptions) that every bee has the same genes. What is actually being discussed in this discussion are alleles (the actual genetic material located in the physical position that is the gene). For the most part all breeding efforts focus on selecting a phenotype that the breeder likes. The phenotype may be associated with a specific allele or a combination of alleles that are linked to the trait. The phenotype is the physical expression of a trait.. a genotype is the actuall genetic makeup of an organism. However phenotypes need not be 100% linked to genotypes. To beekeeper... the genotype stuff really is not important since beekeepers are typically selecting for expressed phenotypes.

To help others following this thread.... (a slight simplification)
We have a gene for eye.
There are 2 alleles (blue and Brown)
If your alleles are blue/blue your phenotype for eye color is blue - your genotype is homozygous blue
If your alleles are blue/Brown your phenotype for eye color is Brown - your genotype is heterozygous blue/Brown
If your alleles are Brown/Brown your phenotype for eye color is Brown - your genotype is homozygous Brown
(making it more complex (and is not 100% accurate but makes this understandable)
If your alleles are blue/blue AND you have another specific allele (we will call it X) in another gene (we will call it Z) then your phenotype is Green but yet your genotype is homozygous blue.

Also some phenotypes can be the result of specific environmental experiences (triggers) or other "non-genetic" but molecular based reasons (I am not a honey molecullar biologist) but I know many species have DNA methylation transferred through maternal lineage. Methylation can have huge impacts on gene expression and huge long term impacts on phynotypes... look up Fetal Programming... a lot of research is showing that an individual can be "programmed" for significant later life health issues (like Type 2 diabetes) by his/her mom based on her diet during sometime around the 2nd trimester. Things like high salt/high fat diets during this period can "almost ensure" the child to develop Type 2 diabetes.

And "jumping genes" (transposons - both retro and non-retro) were discovered and defined by classical genetics by Barbara McClintock without even knowing what DNA was at the time... here research predates all of that stuff...


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## WLC (Feb 7, 2010)

Hmm...

Epigenetics, transgenerational immune priming, transposons, and DNA methylation...

There are quite a few Honeybee genetics studies on those issues in my Mendeley Desktop.

My students are working on their DNA barcoding proposals in collaboration with McClintock's former institution, Cold Spring Harbor.

So many positive waves...


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## Rick 1456 (Jun 22, 2010)

WOW!
I have read this thread several times. I was wondering if I could get college credits having done that.
In all seriousness, I wish I was somewhat fluent in genetics. I had it in college but counting red kernels on a yellow cobb is not in this league. Thanks for the breakdown on dominant and homozygous. It helped. I do think I have a grasp/ not necessarily a true understanding, but I love this arena. Anyone that understands/studies this and can put it in laymens terms and will post, you have my undivided attention. It is fascinating.
Thankyou


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## WLC (Feb 7, 2010)

The same kind of reasoning would apply to 'Ms. Queen, who's your mommy?'


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## deknow (Jul 17, 2006)

WLC said:


> As long as there's an average of 4 or 5 recombination events per chromosome pair every time a gamete is produced, asking the matrilineal vs patrilineal question for a specific trait becomes 'iffy' at best.


Iffy? If that were the case, breeding bees for specific traits would fail, even when using II. Given that breeding efforts do seem to work (and have for hundreds of years), I'm not sure the term "iffy" applies.

deknow


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## llang (Aug 13, 2010)

WLC -

Figure your numbers came from here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626635/?tool=pubmed

deknow - I think the "iffy" is because with the rate of recombination... all the chromosomes should "move" to be the same over time... aka stabilize...

After reading the paper.. it got me thinking... the concept that caught my eye is that honey bees are actually a small breeding population but cover a large area. This could easily result in rapid speciation over short periods of time. Simple short-term environemental barriers could result in diverence.. and new species... (think African Ciclids).

Clearly there is a strong selective pressure to prevent this and to maintain the species as a "whole" as it were... the "solution" is seriously increase recombination to prevent speciation...


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