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Polygenic Inheritance and Mendel

Genetics as it applies to evolution, molecular biology, and medical aspects.

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Polygenic Inheritance and Mendel

Postby menudoluver » Wed Dec 10, 2008 1:46 am

how does Polygenic inheritance deviates from Mendel's conclusions?
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Postby mith » Wed Dec 10, 2008 5:19 pm

look at his laws
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Enjoying one moment at a time;
Accepting hardships as the pathway to peace;
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Postby keenangp » Sat Dec 13, 2008 2:46 am

Does it deviate from Mendel's conclusions? Mendel knew he was experimenting with traits which would yield precise results, he stayed away from more complicated, inexplicable inheritance patterns.

I think... That polygenic inheritance involves independent assortment and segregation, it's just kind of compounded, yielding quantitative traits instead of precise traits.
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Postby MrMistery » Sun Dec 14, 2008 2:11 am

actually mendel was just lucky. He didn't know anything at the start of his experiments...
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Re:

Postby MichaelXY » Sun Dec 14, 2008 8:27 am

MrMistery wrote:actually mendel was just lucky. He didn't know anything at the start of his experiments...


I would not call it luck. I also would not say he did not know anything. I am sure he must have made previous observations which led him to conduct his experiments on peas.
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Postby MrMistery » Sun Dec 14, 2008 5:41 pm

he may have, but there is no evidence he did.
Actually two of the characters mendel observed were not monogenic, but were controlled by two genes.
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Re: Polygenic Inheritance and Mendel

Postby Darby » Mon Dec 15, 2008 4:14 pm

The circumstantial evidence that he knew what he was dealing with is huge. After all, he had been growing peas for his monastery, and to do his tests he needed to isolate types within plots and get them to the point where they always bred true for particular traits - just to do that, he had to have had a pretty good idea of what was going on.

I often wonder what the rest of the monks thought about his obsession with pea traits, and just how much acreage they let him use for his allele and generational plots.
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Postby MrMistery » Mon Dec 15, 2008 4:47 pm

Ok, let me rephrase that. Mendel chose characters specifically to be qualitative. He wanted to have only 2 possibilities: either red or white flower, either yellow or green bean etc. I don't think there is any evidence that he knew what was going on beforehand. Of course that is how most experiments are done nowadays, but I don't know if that's how mendel did it.
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Re: Polygenic Inheritance and Mendel

Postby egocentrism » Tue Dec 16, 2008 2:36 am

back to the main question here , how we relate polygenic inheritance with Mendelian inheritance & independent assortment !
I have two points to make , first we have to admit that not all characters that belong to peas are actually work like the 7 characters that Mendel chose , I think he noticed some wrong observations in his work which he couldn't understand or solve he just concentrated on the main two laws of his , and the the facts of 9:3:3:1
anyways he may ignored it somehow , It happens specially that it's a new method and new prospective , gene concept didn't exist , and the theory of gene effects also was unknown so ...
now , It's been noticed that characters that came from one gene or -controlled by one gene - can have the same appearance to monohybride rate , which is 3:1
like
peas -colored flower and coat × white flower and coat
F1 colored flower and coat
F2 3/4 colored -1/4 white
P AA×aa -----F1 Aa ------F2 3 AA-Aa-Aa 1aa
that's the connection I guess , monohybride cross !!!
:shock:
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