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Post by sophiasmith on Jan 31, 2019 14:34:14 GMT
Members of a FB group are refusing to believe that there is any danger in inbreeding degus. And that breeding degus for color does not have any ill effect on their genetic health. There's also the question, are all non-agouti degu inbred or are there some "safe" colors/breeders. Any sources you can give on any of these questions/topics would be greatly appreciated.
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Post by deguconvert on Jan 31, 2019 16:18:17 GMT
WOW! Genetics are not really my forte, but we do have some members that are most excellent. I know this has been a topic on here, but I can't remember if we had resources readily at hand. Sounds like a project and a new sticky to create. I cannot think of a single instance where inbreeding in any closed animal grouping is not found to result in multiple compromises in the health and physiology of the offspring that result. So . . . just doing a very brief and quick google . . . here is a link to look at? www.jstor.org/stable/2386104 . And here is another study done on rodents. www.vortex10.org/Lacy/Reprints/Impacts%20of%20Inbreeding%20Natural%20&%20Captive%20Populations.pdf
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Post by moletteuk on Jan 31, 2019 17:53:43 GMT
Sounds about right for the facebook groups, they will argue black is white all day long and delete your scientifically backed up facts that don't suit them. So, don't get your hopes up that you can convince them of anything that they don't want to hear. A couple of members from here have been operating more by stealth dropping snippets of facts here and there to try to spread some truth without getting deleted or banned.
The difficulty is getting scientific proof specific to degus, there is very little out there. Basically, any animal that is inbred too much will result in increased birth defects and susceptibility to illness through lack of genetic diversity.
Every non agouti degu is considered by this forum and by the german forums (deguforum.de) to be less healthy than agoutis. Our forum and their forums have been active for many years (10yrs+) and our forum has had long standing moderators over this period who monitor all activity and we have certainly seen increased health issues as time has gone on and non agouti degus have become more prevalent. Deguforum.de take the matter so seriously that they have banned photos and any discussion at all that could be interpretted as promoting any non agouti degu colour. Before the patched degus turned up we would see a lot of blue degus and there was a consensus that they were smaller and less healthy. Probably the majority of shop bought degus over the last couple of years have been patched, there are probably so many now that it's difficult to know what to compare them to, the agoutis coming from the same shop have been through the same (in)breeding process and so have just as little genetic diversity, they just don't happen to carry the pattern gene (allele).
The blue allele is recessive so requires both parents to be carriers to produce a blue, so techinically requires more extreme inbreeding. The pattern allele is not thought to be recessive so only requires one parent to be a carrier so requires less inbreeding. The thing is I wouldn't trust the pet shop suppliers not to just totally line breed anyway. The rarer the colour, the more likely it is to be recessive and the more likely it is to be more intensively line bred and less healthy otherwise they would have been able to expand the quantity living by now.
As far as this forum is concerned there aren't any responsible breeders of degus in Britain because there are already so many in rescues that it is irresponsible to breed more when there are already many looking for homes.
Somebody else may be able to point you to some scientific references.
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Post by savvy on Jan 31, 2019 18:25:39 GMT
Isn't it winic1 who knows a lot about genetics?
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Post by winic1 on Jan 31, 2019 19:01:54 GMT
Yes, I have two degrees in biology, emphasis in genetics on the second one. Will read through the above a little later today. Spent a couple hours at the eye doctor this morning, and I'm beat.
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Post by winic1 on Feb 1, 2019 0:27:40 GMT
There is danger in inbreeding ANYTHING. Animals AND plants.
We have, oh to give a round number, bajillions of genes. All higher (diploid) creatures have two copies of each gene, one set from the female parent, one set from the male parent. Some traits are controlled by just a single gene, but most are determined by a bunch of genes all interacting together. Some genes affect more than one trait, for example, a gene that controls the structure of your collagen is going to affect skin, cartilage, tendons, bones, and ligaments, to name just the major parts, so if it goes bad, lots of things go bad.
Fortunately, by having two copies of every gene, if one copy goes bad (mistakes can happen when cells are dividing/growing) you have the other copy that might cover it up and still do its job correctly. And if a bunch of genes work together to make or control some body part, the chances that all the good genes can cover up the effects of the bad gene are pretty good.
So, everyone has bajillions of genes, and some of them are bad, messed up, corrupted, deleterious, just plain wrong in some way. But you have so many good genes, they don't matter too much. As each creature reproduces, it passes on half of its genes, one complete set, but that set is a random mix of copy 1 or copy 2 of each gene. This is why siblings don't come out identical (except for identical twins, which start from a single set of genes), because you get a random half of each of your parent's genes.
Now, when a creature reproduces and passes on half its genes, of course, some of its bad genes are going to be passed on, too. Not usually much of a problem, unless its mate also happens to have that same bad gene, and passes it on, so the offspring gets two bad copies of a gene. Then there is no good gene to cover up the defective one, and the problem caused in that trait shows up.
When you inbreed, you can end up concentrating the bad genes. Dad has 5 bad genes and passes on 4 of them to son. Mom has 5 different bad genes, and passes on 3 of them to this son. Son now has 7 bad genes. Son breeds back to mom. She passes on all 5 bad genes to grandson, and Son passes on 6 of his, including the same 3 he got from Mom. Grandson now has 11 bad genes, and 3 PAIR of bad genes, causing 3 bad traits to show up. Grandson breeds to an aunt of his, sister of his parent "Son". Sister had gotten only 2 of Dad's bad genes, but 4 of Mom's, so she has 6 bad genes. She only passes on 2 bad genes, but Grandson who she has mated with, who has 11 bad genes and 3 of them pairs, will definitely pass on the 3 bad genes (because he has no good copy of them) and say, 4 of the other for a total of 7, but the chances of these bad genes matching the bad ones from Sister are getting higher, since they both had the same source of them in the first place with Dad and Mom.
So, the bad genes end up running into each other with each inbreeding. And the numbers rise. And the chances of getting both copies of the gene for a trait being the bad ones, rises. And therefore the health of the creature decreases, as might the size, the intelligence, the ability to reproduce, the susceptibility to diseases, cancers, metabolic disorders, etc.
Even without considering the bad genes, inbreeding tends to reduce the variability in an organism's genetic make up, if you aren't introducing new genes from unrelated beings, you quickly end up with limited gene types. Why is this a problem? It's the variability in genetic make up that allows organisms to adapt and handle new conditions, environments, stresses, diseases, etc.
Then, there's another problem that can result from inbreeding for specific traits, such as color. Suppose a gene mutates (changes randomly) and that creates a new coat color in degus. This new color, in and of itself, is no problem at all for the organism. There's no problem with a degu having both genes for this color present in their genetic make up. Great, right? Yeah....until a gene very close to that color gene, maybe right next to it on the chromosome, mutates to something bad. Something that, if you get two copies of it, makes the degu very sick. Or is lethal since it messes up a trait that is critical to development or life. So, if you get two copies of this very bad gene, you are in big big trouble, or never even make it to being born. Now, genes that are very close to each other on a chromosome tend to stick together. When the genes are randomly dividing themselves into sets so that the egg or sperm gets one set, ready to combine with the other parent's sperm or egg, it's kind of like having a necklace of beads(but glued on to the string so they stay put), and you clip the two strings in a few places and switch some sections, so whole sections of beads stay together. So do whole sections of genes on the chromosomes.
So if your new fur color is next to a really bad gene, as you breed for that color, and inbreed siblings, parents, relatives of that color, your chances of giving the offspring two copies of that really bad gene become very very very high, since it travels along with that color. And even if the offspring don't get two copies of that bad gene, they are almost guaranteed to get one copy. So a bad gene that would have been uncommon in general, is now getting accidentally deliberately spread throughout the population. People learn "you don't breed Purple to Purple or half the offspring die", sure, so they breed purple to normal, then breed those offspring back to purple or to each other, knowing the purple will show up again. But every time purple gene is passed on, so is the bad gene, and now it's hiding in many of the normals, also.
So, inbreeding of ANY organism tends to concentrate bad/defective/deleterious genes.
Period.
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Post by winic1 on Feb 2, 2019 8:02:17 GMT
Now, of course, you could get lucky with inbreeding and get only good traits passed on, and have a perfectly healthy animal. Genetics is like a giant lottery of genes--when you randomly pull lottery numbers, sometimes someone wins. But mostly, you are going to be cutting down on the range of diversity in the genetic pool, and concentrating (increasing) the frequency of the bad genes and/or bad gene combinations. A technique commonly used in plant breeding (because plants seem to be more tolerant of extreme inbreeding) is to use extreme inbreeding to then develop what is called "hybrid vigor". You create an extremely inbred line of the plant you are working with--inbreed for many many generations, until you are pretty sure you have bred out all variability in the genes, and generally by this time you have a very small, weak, stunted version of the plant. You create a second, completely separate and different inbred line of the same species of plant, until again, you are sure you have bred out all variability in the genes of that one, and hopefully completely different than the first one, and again, end up with a small, stunted, weak version of the plant. Then you breed these two very inbred plant lines to each other. At this point, since each parent plant had very different genes present, the pairs of genes of the offspring are completely mixed up, and you get a super plant of amazing quality, size, vigor, etc., a hybrid with great genetics and great traits. To give a visual example of the genetics of this, suppose the genes of the plant, which come in pairs, are labelled with the alphabet, A through Z, so you have AA BB CC. Only, since you can have different versions of each gene (red flowers, pink flower, white flowers/dark green leaves, medium green leaves, light green leaves, spotted leaves...) the genes would be more like for A you could have: A,a,A,a,A,a, etc, and the same for B, and C... so a typical, genetically diverse individual might be AA Bb cC dd ee Ff gG hh.... When you inbreed the line to the extreme, you end up with, for example, AA BB CC DD EE FF....
and maybe your second inbred line is aa bb cc dd ee ff.....
o then when you cross breed them ('hybridize' them) you get
Aa Bb Cc Dd Ee Ff and every gene is now back to completely variable combinations, and you get a super-being, the "hybrid vigor" being expressed.
So, IF you could get degus of various colors, which we know are probably inbred in order to selectively have increased the numbers of that color, from say widely different areas such as different countries, and breed them, you would essentially be conducting a breeding program such as just described. By cross-breeding what are very separate inbred lines, it might be possible to breed out the observed weaker constitutions of inbred, color bred lines. However, you would have to continue being very careful to breed unrelated lines to maintain this newly improved genetic diversity. And if the situation of lethal or severely deleterious genes being linked closely to a color gene does exist, then breeding for genetic diversity or hybrid vigor is not going to make a difference, because those very bad genes are going to be sitting there next to the desired genes no matter how carefully the breedings are selected.
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Post by winic1 on Feb 2, 2019 8:04:59 GMT
So, did I make sense? Can you follow what I describe? I tried to use plain english and not too much biology-ese. If I wrote it out in genetic terms, you'd probably say "it's all greek to me" and you'd be right. (if there are any other biologists out there, you'll get that one!)
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Post by sophia on Feb 3, 2019 4:15:18 GMT
There is danger in inbreeding ANYTHING. Animals AND plants. We have, oh to give a round number, bajillions of genes. All higher (diploid) creatures have two copies of each gene, one set from the female parent, one set from the male parent. Some traits are controlled by just a single gene, but most are determined by a bunch of genes all interacting together. Some genes affect more than one trait, for example, a gene that controls the structure of your collagen is going to affect skin, cartilage, tendons, bones, and ligaments, to name just the major parts, so if it goes bad, lots of things go bad. Fortunately, by having two copies of every gene, if one copy goes bad (mistakes can happen when cells are dividing/growing) you have the other copy that might cover it up and still do its job correctly. And if a bunch of genes work together to make or control some body part, the chances that all the good genes can cover up the effects of the bad gene are pretty good. So, everyone has bajillions of genes, and some of them are bad, messed up, corrupted, deleterious, just plain wrong in some way. But you have so many good genes, they don't matter too much. As each creature reproduces, it passes on half of its genes, one complete set, but that set is a random mix of copy 1 or copy 2 of each gene. This is why siblings don't come out identical (except for identical twins, which start from a single set of genes), because you get a random half of each of your parent's genes. Now, when a creature reproduces and passes on half its genes, of course, some of its bad genes are going to be passed on, too. Not usually much of a problem, unless its mate also happens to have that same bad gene, and passes it on, so the offspring gets two bad copies of a gene. Then there is no good gene to cover up the defective one, and the problem caused in that trait shows up. When you inbreed, you can end up concentrating the bad genes. Dad has 5 bad genes and passes on 4 of them to son. Mom has 5 different bad genes, and passes on 3 of them to this son. Son now has 7 bad genes. Son breeds back to mom. She passes on all 5 bad genes to grandson, and Son passes on 6 of his, including the same 3 he got from Mom. Grandson now has 11 bad genes, and 3 PAIR of bad genes, causing 3 bad traits to show up. Grandson breeds to an aunt of his, sister of his parent "Son". Sister had gotten only 2 of Dad's bad genes, but 4 of Mom's, so she has 6 bad genes. She only passes on 2 bad genes, but Grandson who she has mated with, who has 11 bad genes and 3 of them pairs, will definitely pass on the 3 bad genes (because he has no good copy of them) and say, 4 of the other for a total of 7, but the chances of these bad genes matching the bad ones from Sister are getting higher, since they both had the same source of them in the first place with Dad and Mom. So, the bad genes end up running into each other with each inbreeding. And the numbers rise. And the chances of getting both copies of the gene for a trait being the bad ones, rises. And therefore the health of the creature decreases, as might the size, the intelligence, the ability to reproduce, the susceptibility to diseases, cancers, metabolic disorders, etc. Even without considering the bad genes, inbreeding tends to reduce the variability in an organism's genetic make up, if you aren't introducing new genes from unrelated beings, you quickly end up with limited gene types. Why is this a problem? It's the variability in genetic make up that allows organisms to adapt and handle new conditions, environments, stresses, diseases, etc. Then, there's another problem that can result from inbreeding for specific traits, such as color. Suppose a gene mutates (changes randomly) and that creates a new coat color in degus. This new color, in and of itself, is no problem at all for the organism. There's no problem with a degu having both genes for this color present in their genetic make up. Great, right? Yeah....until a gene very close to that color gene, maybe right next to it on the chromosome, mutates to something bad. Something that, if you get two copies of it, makes the degu very sick. Or is lethal since it messes up a trait that is critical to development or life. So, if you get two copies of this very bad gene, you are in big big trouble, or never even make it to being born. Now, genes that are very close to each other on a chromosome tend to stick together. When the genes are randomly dividing themselves into sets so that the egg or sperm gets one set, ready to combine with the other parent's sperm or egg, it's kind of like having a necklace of beads(but glued on to the string so they stay put), and you clip the two strings in a few places and switch some sections, so whole sections of beads stay together. So do whole sections of genes on the chromosomes. So if your new fur color is next to a really bad gene, as you breed for that color, and inbreed siblings, parents, relatives of that color, your chances of giving the offspring two copies of that really bad gene become very very very high, since it travels along with that color. And even if the offspring don't get two copies of that bad gene, they are almost guaranteed to get one copy. So a bad gene that would have been uncommon in general, is now getting accidentally deliberately spread throughout the population. People learn "you don't breed Purple to Purple or half the offspring die", sure, so they breed purple to normal, then breed those offspring back to purple or to each other, knowing the purple will show up again. But every time purple gene is passed on, so is the bad gene, and now it's hiding in many of the normals, also. So, inbreeding of ANY organism tends to concentrate bad/defective/deleterious genes. Period. This is fantastic. Crystal clear. (Although you're preaching to the choir) I think anyone could understand this. I'd love to quote you...if that's ok please let me know how to credit you.
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Post by sophia on Feb 3, 2019 4:35:47 GMT
Winic1 your second comment re inbreeding down to AA BB etc then mating to aa bb etc. Is that "outbreeding"? And I noticed you used plants as an example, wouldn't it be incrediby unethical to breed down to essentially genetic zero creating generations of sicker and sicker animals to get it as bad as possible to bring it back? Is it even possible?
Our breeders like to claim that they are making stronger animals by importing from (mostly) Germany and Eastern Europe. That doesn't make sense to me because in the USA/Canada where we are located I don't know of anyone outside the Universities with a full pedigree. So I can only assume that they are importing one from Germany and one from Chechzslovakia (I did my best lol) pairing those 2 and hoping for the best, and they are not spending $1000/degu to import Agouti. Besides being a small community (colored degus) so how much genetic difference can there be if 50 breeders (very high guesstimate) with 100 animals keep swapping the same 5000 animals across the globe?
Has the degu genome been sequenced and is there testing. (That seems absurd) but a $1000 degu seems absurd when there are plenty available.
Thank you so much for your time in answering, I really appreciate it.
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Post by sophia on Feb 3, 2019 4:44:35 GMT
And Mole, I forgot to say that I am an admin and we have (by sheer good fortune) a fantastic admin team. We do not delete science, we make files about it. We are only held back by a desire to create a community for everyone. Although the most egregious breeding practices (coupled with an overall bad attitude) have had one member removed. So hopefully things are changing in the FB scene. Not that we don't run for a more rational hideout when things get nuts.
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Post by winic1 on Feb 3, 2019 7:20:37 GMT
Of course you can quote me. Anything to help spread a little genetic knowledge and dispel a little Dark Ages mentality. I keep finches, and in the bird community the way they talk genetics is downright mindblowing! They actually understand many of the concepts, but they refuse to use the right terminology, or that there's more than one way for genetic inheritance to happen, so there is so much absolute garbage ruining the knowledge they do have; and a few loudmouthed self-declared experts just shout down anyone who tries to say anything they don't know themselves. SO frustrating!
Yes, it's "outbreeding". Or, if you know you have specific genetic lines, "cross-breeding". I used plants because this is a technique commonly used in plant breeding. Plants tolerate you messing with their genetics much better than animals do. You can really take many plants to an extreme with genetic manipulation--one set of chromosome instead of the paired two sets that is normal (haploid instead of diploid) or multiple sets, three, four, six, eight (triploid, tetraploid, hexaploid, octoploid). You can grow a tissue culture line from plant tissue, a mass of cells in a culture dish in a lab, and then when you're ready get it to grow back into plants again, plants you can put into dirt and that will flower and set seed and make more plants.
Animals, higher animals with feet and feathers and fur (vs tiny little microscopic or wormy type things) don't tolerate you messing with their genetic makeup very well. You run into non-viability very quickly if you try to do many of the things you can get away with in plants. And yes, the ethics of inbreeding or linebreeding to an extreme, creating a very weak, sickly creature, so that you could then crossbreed it, are highly questionable (although a botanist might argue that plants are people too, just because they don't have big brown eyes to look sadly at you with doesn't mean they aren't aware of what you're doing to them).
If the breeders here want to increase genetic diversity to make a stronger genome, they should be importing degus from other countries, and breeding them to the American and Canadian ones. Better yet, get some wild ones from a variety of locations in Chile as well. Really mix things up. Definitely don't just breed the color variations together even if they did come from other places, breed them to the most distant agoutis possible, then carefully choose from those hybrid offspring to breed and have the color come back out. Constantly outbreed to normal (agouti) types, then bring the color back out in the next generation again by crossbreeding these who now carry the color genes.
So every other generation would be to bring out color, and the inbetween generations would be to outbreed to normal types to mix up the genes. You get far fewer of the color types coming out of this plan, you see more agouti, but many of them will be carrying the color genes, so eventually you have spread the color genes far and wide, and the other colors will show up more often. But to do it right, and responsibly, you should constantly outsource both color and agouti types to make sure you keep the genetic diversity going--whether you source degus from Connecticut and Texas or Germany and England, keep mixing them up from far away places where they are not likely to be related to each other.
{what do you mean when you ask how to credit me? a name to use, credentials to prove I might know what I'm saying and not just making it all up for fun? }
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Post by winic1 on Feb 3, 2019 7:36:28 GMT
Curious, where are you, in the US/Canada? I'm in New England, nearer the New York end.
And did somebody (or group, institute, university, etc) really spend $1000 bringing over foreign degus?
A quick search for "Octodon degu genome" does bring up some hits, so it looks like there might be some partial or basic genome sequencing done already. Not a whole lot, I'd guess. And unfortunately there is a gene called "DegU" that has nothing to do with degus at all, that's just its designation, that has evidently been heavily studied, so it makes searching for Degu genome information more difficult as if you aren't careful with what you search (hence my using their scientific name) you get swamped with things about this particular gene, not degus.
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Post by bouncy on Feb 3, 2019 8:56:33 GMT
If you want to apply the explanation to a good example, look at pedigree dogs! The breeds we know today are completely different to 100 years ago. They consistently inbred to bring out specific traits (colour, features), and now many popular breeds have inherited health defects. Pugs and pekingese have breeding difficulties, GSD have inherent spine and joint arthritis, and as for British bulldogs, which sadists deliberately changed a dog so that it struggles to breathe, has heart problems, and has legs 1/3 the original length that are under such strain they've been forced to bow outwards......... en.wikipedia.org/wiki/Pedigree_Dogs_Exposed If it applies to dogs, it transfers directly to Degus!
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Post by moletteuk on Feb 3, 2019 11:14:20 GMT
And Mole, I forgot to say that I am an admin and we have (by sheer good fortune) a fantastic admin team. We do not delete science, we make files about it. We are only held back by a desire to create a community for everyone. Although the most egregious breeding practices (coupled with an overall bad attitude) have had one member removed. So hopefully things are changing in the FB scene. Not that we don't run for a more rational hideout when things get nuts. That's fantastic, I'm really happy to hear this. Do you mind me asking which group it is?
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Post by sophia on Feb 3, 2019 15:36:21 GMT
Degu Usa. We have a wild mix of people in the general group from beginners to lifelong exotic owners/wildlife rehabbers and of course a few breeders. We try to be open as long as conversations remain civil. Hope to see you.
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Post by sophia on Feb 3, 2019 17:02:10 GMT
Winic1 I'm from Upstate NY on lake ontario. When I say credit you I mean the authorship aka by winic1. I could credit you personally deguworld.proboards.com your facebook, or nothing. It's very well written the science bears out regardless of your credentials. Although they are nice to have. And yes $1000/DEGU (singular) $600 usd to ship from e.u. $400+/specimen. Because at that price point they aren't really degus are they? An agouti w pedigree is $45 and a black can go $400-$600 USD so you can see the profit motive. So basically they're going bankrupt shipping genetically depressed degus back and forth to each other. Cause no one in their right mind would pay that. Ironically the whole controversy popped off when our group posted a general overview on breeding. Our opinion was DON'T and we pointed out (for deterrence) that most degu in the US are rehome at $30/pair. Well one breeder in particular flipped out. You would too if you spent $1000/degu . and sold at $400..
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Post by deguconvert on Feb 3, 2019 17:48:57 GMT
WOW!! That's mind boggling!!
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Post by sophia on Feb 3, 2019 19:59:24 GMT
We were all pretty flabbergasted when a breeder agreed to talk with us and share her pricing and expenses. We had no idea.
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Post by winic1 on Feb 8, 2019 16:58:30 GMT
you can just credit me here, as winic1, if you want. I have a BS in biology, with minor in chemistry/physics/math. MS in Botany/Cytogenetics. BA in Chemistry. Variety of both lab, industry and field research work over the years. And then my overly educated, overly scientific mind constantly continuing to read and learn. On paper, I'm very impressive.
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