Sex alleles

[Finman]

Tupla
.

 

[Finman]

Nope, in my opinion, correct definition of drone is bee with one allele whether haploid or diploid.

Well said!

.

 

[Beefriendly]

Nope, in my opinion, correct definition of drone is bee with one allele whether haploid or diploid.

A diploid drone has 2 copies of the same allele, so it has 2 alleles [pedant mode off].
In answer to OP question, they are discovering new sex alleles all the time. So the number found probably reflects the date that particular review about sex alleles was written.

 

[Finman]

A diploid drone has 2 copies of the same allele, so it has 2 alleles [pedant mode off].
.

IT has not, because it is dead.

As dead as Tamar Valley AMM on Ice Ace tundra, where they eveloped millions years ago.

XXXXXXXXXXXXXXXXXXXXXXXXXXXX

Diploid drones

Normally drones develop from unfertilized eggs and are haploid. Diploid drones (called also "biparental males") develop from fertilized eggs [1][2] which are homozygous at sex locus. In nature diploid drones do not survive until the end of larval development. The larvae of diploid drones are eaten by workers [3] within few hours after hatching from egg [4] despite the fact that they are viable [5][6].

Adult (imago) diploid drones can be reared in laboratory by hatching eggs in incubator and feeding larvae with royal jelly without workers [7][8]. The larva can be transferred to colony after 2-3 days. At this age workers feed them normally. Diploid drones can be reared also in autumn in mating nuclei with about 1000 workers [9].

Externally adult diploid drones are similar to haploid drones. In comparison to haploid drones diploid once are larger, heavier [10][11][12] but see [13][14], have smaller testes [15][14], fewer testicular tubules [16], fewer wing hooks [14] and lower vitellogenin concentration [14]. Diploid drone larvae produce more cuticular hydrocarbons than workers but less than haploid drones [17] but see [18].
Diploid drones produce diploid spermatozoa [19] containing twice as much DNA as haploid spermatozoa [20][14]. Diploid spermatozoa are longer than haploid spermatozoa; their head is particularly long [21]. Ultrastructure of haploid and diploid drones is similar [22]. In theory triploid honey bees can be obtained by inseminating queen with diploid spermatozoa [21], however, this was not achieved so far because of small number of sperm produced by diploid drones.

Workers recognize the diploid drones larvae using substances present at their bodies [23]. It was suggested that diploid drones produce pheromone called "cannibalism substance" which is a signal to workers that they should be destroyed [23] see also [24]. Such self-destructive behaviour of diploid drones can evolve because they are neither able to reproduce nor help their relatives. Eating of the diploid drones at early stage of larval development allows to save valuable resources and produce bigger number of their relatives. However, no cuticular compound specific for diploid drone larvae was found [17]. First instar larvae of haploid and diploid drones differ in relative amount of cuticular compounds [17] and the difference can be used by workers for detection of diploid drones. In older larvae the differences in cuticular compounds are smaller [14].

In natural conditions frequency of diploid drones (before destruction by workers) in a colony is 0.05±0.03 (mean±SD) [25]. The frequency can be much higher in case of inbreeding. In colonies with large proportion of diploid drones there is "shot brood" - brood of different ages scattered irregularly on a comb [26][27][28][29]. Multiple mating by the queen leads to reduced variance of proportion of diploid drones present in the colony [30].


amount of alleles Everything You Wanted to Know about Honeybee Sex

Joseph Caspermeyer*,1


+
Author Affiliations
1MBE Press Office
↵*Corresponding author:
E-mail: [email protected].

ARTICLE

There is an exquisite genetic control behind a honeybee’s fate in the hive—from the lowly drone to the almighty queen—which literally represents the bee’s knees for evolutionary scientists exploring how multiple mutations, or alleles, of a single gene called the complementary sex determiner (csd) can have a profound influence on honeybee society.

Unlike people, there are no X and Y sex chromosomes for bees. Rather, sex is determined by csd gene and its allelic composition and whether a queen bee chooses to fertilize her eggs. Female bees (queens or workers) come from fertilized eggs, always receiving two different (heterozygote) copies of csd. Fertile males always come from unfertilized eggs, receiving only one copy of csd. Two identical (homozygote) copies of csd in fertilized eggs is always lethal; these individuals are being killed at the early larval stage by worker bees as they would develop into diploid males which do not contribute to colony fitness.

Lechner et al. (2013) have now examined the exquisite molecular control behind the sex determination, finely identifying and tracing back a comprehensive number of csd alleles to create a richer understanding of the variability of the csd gene over evolutionary time. They looked at a data set of 244 csd sequences from queens, worker bees, and drones and showed that the total number of csd alleles found in bees ranges from at least 53 (locally) to 87 (worldwide), which is much higher than previously reported. Using an evolutionary model, they also extrapolated the presence of a total 116–145 csd alleles worldwide, a great example of the enormous sequence variability within csd. They were able to finely decipher the minimum number of mutations leading to heterozygous csd, identify faster evolving hot spots within the csd gene, and how these may contribute to variability.

“Comprehensive insights into the sequence variability of the sex determining gene csd in honeybees elucidate the evolutionary processes that lead to the enormous number of csd alleles found worldwide,” said Hasselmann.

Finally, they traced the data back over evolutionary time and found that a novel csd function affecting sex determination arises about every 400,000 years. The study provides one of the most comprehensive views of the enormous genetic diversity and the evolutionary forces shaping sex determination in bees, as well as how changes in csd affect honeybee colony fitness.
© The Author 2013. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: [email protected]


in the year 2013 it was evaluated 87 alleles in sex genes worldwide,

http://mbe.oxfordjournals.org/conten...ev.mst232.full


Scientists Find Genes That Let These Bees Reproduce Without Males

http://www.nytimes.com/2016/06/10/sc...rica.html?_r=0

The female Cape bee is a renegade. She breaks all kinds of rules and disregards orders. In this isolated subspecies of honey bees from South Africa, female worker bees can escape their queen’s control, take over other colonies and reproduce asexually — with no need for males. Scientists identified the genes most likely to have instigated this unusually powerful worker bee behavior, according to a study published Thursday in PLOS Genetics.

About Cape bees

http://entnemdept.ufl.edu/creatures/..._honey_bee.htm

 

[Erichalfbee]

Yes......My genetics is rusty...I have some reading to do

Third caste is surely drone.


.

No
The Queen and the Drone are responsible for reproduction and are female and male.
The queen and workers are the same gender but sufficiently different in appearance and function as to be different castes.
The Drone is not a caste though he is commonly described as such

 

[Finman]

The Drone is not a caste though he is commonly described as such

a job to do

How to Identify the Three Castes of Bees

0470430656.jpg
Related Book

Beekeeping For Dummies, 2nd Edition




October 2015 - Columbiana and Mahoning County Beekeepers ...



www.columbianamahoningbeekeepers.org/wp.../Skep-Oct15.pdf



Bee Castes. There are ... three castes of honey bees are interdependent for the colonies ... https://agdev.anr.udel.edu/maarec/honey-bee-biology/the-.

Maarec is a consortion of 6 universities, and scientists use 3 caste system
.



.

 

[Finman]

Yes......My genetics is rusty...I have some reading to do

I bet that mere looking at a picture helps

 

[For want of a better word]

I bet that mere looking at a picture helps

Well Finnie my sweet... that is the numero uno of cut and paste


SO.... if a diploid drone gets eaten as soon as it seen by the cast called workers, how does Science know of its very existence... or is all this stuff and nonsense purely hypothetical dreaming?

Nos da

 

[Finman]

IT is told in the text.
Read it. 2 ways. Very useful.

 

[MuswellMetro]

Well, maybe three, eh Finman?

A diploid female, and a haploid male, and a diploid male. Right? And, it's all about alleles.

It doesn't take 1000. It only takes 2. A bee with two different alleles is a female. A bee with one allele is a male. But what if a bee has two alleles that are identical? A diploid drone, right?

So, what'e the correct definition of a drone? A haploid bee, or a bee with only one copy of an allele?

Asian hornet Diploid drones are fertile so you can get Triploid Asian Hornet Drones..so is that 4

 

[Erichalfbee]

a job to do

How to Identify the Three Castes of Bees

0470430656.jpg
Related Book

Beekeeping For Dummies, 2nd Edition




October 2015 - Columbiana and Mahoning County Beekeepers ...



www.columbianamahoningbeekeepers.org/wp.../Skep-Oct15.pdf



Bee Castes. There are ... three castes of honey bees are interdependent for the colonies ... https://agdev.anr.udel.edu/maarec/honey-bee-biology/the-.

Maarec is a consortion of 6 universities, and scientists use 3 caste system
.



.

I have to disagree with you

The three types of honey bees in a hive are: queens (egg-producers), workers (non-reproducing females), and drones (males whose main duty is to find and mate with a queen). Thus honey bees have two sexes, male and female, and the female bee has two castes, queen and worker. ...

 

[MuswellMetro]

thanks Finman, you found a lead to what we were looking for, you must have a better search engine than me

full txt pdf of research attached

Nucleotide Variability at Its Limit? Insights into the Number
and Evolutionary Dynamics of the Sex-Determining Specificities
of the Honey Bee Apis mellifera

 

[Finman]

I have to disagree with you

The three types of honey bees in a hive are: queens (egg-producers), workers (non-reproducing females), and drones (males whose main duty is to find and mate with a queen). Thus honey bees have two sexes, male and female, and the female bee has two castes, queen and worker. ...

It makes no differency how you classify them.
Nothing practical.

We all know that drones are needed to fertilize virgins.

 

[Icing Sugar]

Hi Dogwednesday,

It is thought that there are about 150 honeybee sex alleles.

The paper you want is:

Lechner S, Ferretti L, Schoning C, Kinuthia W, Willemsen D, Hasselmann M.
Nucleotide variability at its limit? Insights into the number and evolutionary
dynamics of the sex-determining specificities of the honey bee Apis mellifera.
Molecular Biology and Evolution. 2013;31:272–287.

you can find it online if you hunt around enough - at least I did last winter!

I have attached my jottings to this post.

 

[alldigging]

It makes no differency how you classify them.
Nothing practical.

We all know that drones are needed to fertilize virgins.

Only the first one.

 

[Fusion_power]

I spoke to Tom Rinderer about 6 months ago and mentioned that there was research showing about 150 sex alleles worldwide. He was thoroughly surprised thinking there might be as many as 30.

finman, this has a great deal of importance for bee breeding. The more alleles are present in a breeding population, the lower the incidence of diploid drones produced and therefore the healthier the brood appears. This work supports the contention that honeybees in the U.S. have a very narrow genetic base. It also supports the known concern that European bee races have reduced number of csd alleles. One thing we could do would be to carefully select bees with different alleles and cross them into local stocks recovering the different alleles after each generation. The result would be to dramatically increase the number of alleles in local stock.

 

[Finman]

.
It has no meaning, how many sex alleles researches find. It makes no change in practical beekeeping.

Local stock.... It is only a word. I have changed my local stock at least once in 10 years.
Some hate to buy mated queens and some understand to change the genepool.

Hobby beekeepers take burdens of genetics, even if they do not know much about it. In imagination they breed mite resistant bees, AFB resistant bees... No one here in forum is not interested about nosema immune stock.

So, I am sure that number of sex alleles do not bring me more honey.

Nothing what you can do to it, and you will never see them .
.

 

[Finman]

finman, this has a great deal of importance for bee breeding. The more alleles are present in a breeding population, the lower the incidence of diploid drones produced and therefore the healthier the brood appears. This work supports the contention that honeybees in the U.S. have a very narrow genetic base. It also supports the known concern that European bee races have reduced number of csd alleles. .

Fusion. I have a degree in genetics in university and in population ecology. I just say this, that vain to bluff me with allele word. Alleles are mutations. Not more. Some bad and some good, and some meaningless.

Diploid drones. Forget them because they do not exist on hives.

What I am worried about your principle is, that you try to breed your own small population onto very narrow base. But what ever you do it does not harm anything. no. You just do what you like. So do I. I am not doing any great. I just try to exist.

My bee yard has met some bad inbreeding problems, and I am not going to breed my own small population any more. What you can do with 25 hives, you can ruin your bees easily in few years.
But when yoh see that, you buy new mated queens, and nothing worse has happend.
.

 

[Finman]

.
Honey bee has a little bit over 10 000 genes. Each gene may have variation, called alleles.

Human has about 20 000 genes. I did not know this. I read it 10 seconds ago. Number has no meaning to me.

 

[Fusion_power]

If a queen mates with 17 drones - which is the reported average - and there are 17 sex alleles in the local population, then she is statistically likely to mate with at least 2 drones that have sex alleles matching her own. Presuming mixing of the semen in her spermatheca, this means she will lay 1 in 17 eggs as a diploid drone. Six percent of the eggs the queen lays will be disposed of by the workers. Now think about some of those shot brood patterns you sometimes see with no good reason for sealed cells to be so scattered. Lets change the odds. Put 51 sex alleles into the local breeding population. Now when a queen mates with 17 drones, the odds form a statistical curve with very high probability that she mates with no drones having matching sex alleles. 100% of her eggs hatch into workers and the brood pattern is very solid. Take this to the logical conclusion and presume that drone source colonies are typed so that their sex alleles are all ID'd and the breeder queen has sex alleles that do not match any of the drone producers. It does not matter if the drone colonies produce only 2 alleles because all the drone producing queens have the same pair of alleles, so long as the breeder queen's alleles do not match, all of the eggs laid by the resulting mated queens will hatch into viable workers. This concept was proven by Cale back in the 1960's and is a highly effective way to increase honey production by a few percentage points.

You are correct that the average beekeeper can't do much about the sex alleles in his bees. I submit that serious queen breeders should be typing their queens to determine which sex alleles they are propagating and ensure that as many as possible are retained in the breeding population.

Genetics 50 years ago is a long way from what is known of genetics today.

We have a limited number of sex alleles in honeybees in the U.S. I would very much like to see that number doubled or even tripled. Because the sex allele is under reinforced selection, the tendency is to retain diversity in a population.