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Old 04-17-2012
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Genetics Simple Genotype Frequency Calculation

What is the frequency of the Aa genotype and the AA genotype if the frequency of allele A is 0.9%?
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p = 0.9
q = 0.1

prevalence of Aa genotype is 2pq = 0.1
prevalence of AA genotype is p^2 = 0.81
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Quote:
Originally Posted by Dr.NickRiviera View Post
What is the frequency of the Aa genotype and the AA genotype if the frequency of allele A is 0.9%?
Carrier Freq = 2Aa = 2(0.9)(0.1)
Dominet Freq = A^2 = (0.9)^2
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How did we calculate q to be 0.1?
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Quote:
Originally Posted by Valkoff View Post
How did we calculate q to be 0.1?
p^2 + 2pq + q^2 = 1

Allel prevalance is p + q = 1
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Quote:
Originally Posted by johndoe3344 View Post
p = 0.9
q = 0.1

prevalence of Aa genotype is 2pq = 0.1
prevalence of AA genotype is p^2 = 0.81
isn't its more close to .2 than .1?
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To use the p2 + 2pq + q2, it has to be in equilibrium. How would you just assume that the population is in hardy weinberg equilibrium ? Although I'm pretty sure that this is the way to calculate it ...
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Quote:
Originally Posted by Hope2Pass View Post
To use the p2 + 2pq + q2, it has to be in equilibrium. How would you just assume that the population is in hardy weinberg equilibrium ? Although I'm pretty sure that this is the way to calculate it ...
Isn't the this is the case unless otherwise mentioned ?
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Quote:
Originally Posted by Kabutar111 View Post
isn't its more close to .2 than .1?
Yeah it should be 0.18 = 2pq = Aa
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Quote:
Originally Posted by johndoe3344 View Post
p = 0.9
q = 0.1

prevalence of Aa genotype is 2pq = 0.1
prevalence of AA genotype is p^2 = 0.81
Yeah, 0.18, my bad. Left out the 8 =/
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