## Allele to Trait Frequency

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So we just calculated the allelic frequencies up
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here for the dominant recessive alleles, but what
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about the trait itself? How frequent is the
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trait of lactose intolerance in our population? Well,
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about their homozygous dominant and our heterozygous condition,
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they're going to be lactase persistent. And our homozygous
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recessive condition is going to be lactase non-persistent. This
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is the group that's going to be lactose intolerant.
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So, if we calculate the frequency of lactase persistence in my
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population, and we've got 500 plus 350 is 850 total people out
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of 1,000. That's 0.85. Well, look at that! The frequency of the
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dominant allele is 0.675. The frequency of the dominant trait is 0.85.
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They're not the same. This is really
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important, the allelic frequency and the trait frequency
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don't have to match. Take this given
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scenario right here. We have a population of
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1000 people, remember that means we have
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2000 alleles total. And when we calculate our
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allelic frequency, we find that the dominant
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allele for lactase persistence is prevalent at a
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0.75 frequency. The recessive allele is prevalent at at 0.25 frequency.
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When we look at the actual trait frequency, lactase
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persistence comes in at 1.0, 100%. But lactatse
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nonpersistent. The tray to lactose intolerance is 0,
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0%. Now, if these things are true, then I want you to enter a possible number
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of people for each genotype here. Remember, you have
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100 people to choose from, so whatever your numbers you
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put in these boxes, it should add up to a
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1000. Based on the allelic and the trait frequencies that
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you see here, I want you to enter in any
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possible number of people that could be each genotype. Go
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ahead, give it a try. If you get stuck, try
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checking out the forums to see if anyone has some
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タイトル：
Allele to Trait Frequency
Video Language:
English
Team:
Udacity
プロジェクト：
BIO110 - Tales from the Genome
Duration:
02:09
 Cogi-Admin edited 英語(米国) subtitles for Allele to Trait Frequency Cogi-Admin edited 英語(米国) subtitles for Allele to Trait Frequency

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