Posted by:
Warren_Booth
at Thu Nov 4 08:49:47 2010 [ Email Message ] [ Show All Posts by Warren_Booth ]
Hi,
I am happy to answer your questions. First, I have a few of my own.
1) How do you know your litters were parthenogenetic without genetic testing?
2) What were teh circumstances surrounding each litter?
3) How many females produced these litters?
4) What were the ratios of offspring to slugs? Also were they all female litters. What were the litter sizes?
5) Are you willing to provide shed skins from each live animal, tissue from dead? babies, adult females, and any males those "parthenogenetic" litter producing female were with?
I have a few more but will wait for the answers.
Okay, to your questions:
Q1) In Table 1 you list the various loci and micro-sat motifs, but what are the "sequences" you are listing? Are these variable regions within these loci? And, what are the "F" and "R"s? The rest of the table makes sense to me.
A1) The sequences are the microsatellite primers. The F denotes the forward primer, the R, the reverse primer. Each of these pairs amplify a specific region containing an informative (i.e. variable) microsatellite locus.
Q2) And to Table 2, are the numbers listed under each locus (e.g. 295/295) bp lengths and supposed to represent hetero- and/or homozygosity, by length?
A2) Yes, these are the length of the product that each primer pair listed in Table one amplify. If they are the same number, the individual is homozygous at that locus, different means they are heterozygous.
Q3) And also, a question on this statement: "At this stage of development in the sexually produced males examined, both testes and ovaries were present...". Are you saying the similar aged males (to the lone female examined) had both sex organs? Maybe, I missed something or misinterpreted the sentence, or its connection elsewhere.
A3)Yes, this was shocking to us. We used two males and two females from a litter that was the same age to the parthenogen for comparison. The reason being is that many parthenogens have deformed reproductive organs, therefore the deformed hemepenes probe to the depth expected for a female. We needed to confirm that the probed depths were accurately describing the sex. SO, the female sexually produced boas had only ovaries, as did the parthenogen, but the males, interestingly, had both testes and ovaries. We believe (and are examining this further) that the males ovaries degenerate shortly beofre sexual maturity.
Q4) And lastly, you speculate the reason for WW females is the possibility the dam of the litter was hemizygous or was it some meiotic aberration during oogenesis (from the dam)?
A4) We do not believe it is a meiotic disfuntion. The reason being, is that if it were, we would see it in a single egg cell. Not 22 over the space of two years. Additionally, there would be some males produced that did not have this disfunction.
Q5) I lied--here is another. There appears to be some variation in the offspring; can you speculate what is happening? There seems to be some kind of gene shuffling going on. I am not familiar with oogenesis in boids, or terminal fusion for that matter (w/second polar body). If meiosis is occurring, there should be some gene mixing, right?
A5) Well, very basically, as you can see from table 2, the female is heterozygous for multiple loci. When she produces egg cells, they will have one or the other allele at each locus, and that is random. Therefore, there is a 50:50 chance that the egg will get one allele or the other. The end result are a group of egg cells that are genetically variable to each other.
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Sorry, for all the questions. I am just trying to understand every aspect of this paper so I may explain it to my students.
Back to teaching...good work!
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You are very welcome. Feel free to contact me with any further questions you might have. I am glad you enjoyed the paper.
Warren
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Dr Warren Booth / Director USARK
North Carolina State University
Department of Entomology
[ Hide Replies ]
- Parthenogenesis in Boa constrictors - Warren_Booth, Tue Nov 2 19:15:04 2010
- Great Article dr Booth easy for - LarM, Tue Nov 2 19:41:28 2010
- Nice Warren!......... - RuBeN14, Tue Nov 2 20:15:46 2010
- New Scientist write-up - Warren_Booth, Tue Nov 2 20:52:46 2010
- RE: Parthenogenesis in Boa constrictors - boawoman, Wed Nov 3 00:28:01 2010
- More pics - boawoman, Wed Nov 3 00:32:05 2010
- Link to the actual paper - Warren_Booth, Wed Nov 3 07:00:55 2010
- Discovery News write-up - Warren_Booth, Wed Nov 3 07:03:15 2010
- Great article Dr. Booth - ajfreptiles, Wed Nov 3 09:28:27 2010
- RE: Parthenogenesis in Boa constrictors - ALT, Wed Nov 3 10:25:36 2010
- Questions... - creptilia, Wed Nov 3 15:50:31 2010
- RE: Parthenogenesis in Boa constrictors - kblumenthal, Fri Nov 5 12:12:14 2010
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RE: Questions... - Warren_Booth, Thu Nov 4 08:49:47 2010