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Old 10-01-2014
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Default challenging Genetic Q

this q is driving me crazy i dont know how to use Hardy Weinberg in this ?
so please answer with explantation
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is it 0.05?
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I got 0.05
Prevalence=q2=1/100 so q=1/10
Carrier freq= 2q=21/10=0.2

Probability man transmit dis allele=1/2
Probability woman is a carrier=0.2
Probability woman transmit dis allele= 1/2

Multiply....1/20.21/2= 0.05
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Quote:
Originally Posted by Fereshteh View Post
is it 0.05?
yes u r right but explain please?
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Quote:
Originally Posted by excellence View Post
Probability man transmit dis allele=1/2

Probability woman transmit dis allele= 1/2

Multiply....1/20.21/2= 0.05
but how did u get those? and why then multiply?
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Quote:
Originally Posted by swwal View Post
but how did u get those? and why then multiply?
we multiplied because what we need is overall probabality.
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Quote:
Originally Posted by Panmedic View Post
we multiplied because what we need is overall probabality.
Probability man transmit dis allele=1/2

Probability woman transmit dis allele= 1/2

is not supposed to be 25% = 1/4 ?! bcz this is recurrence risk of AR
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Quote:
Originally Posted by swwal View Post
Probability man transmit dis allele=1/2

Probability woman transmit dis allele= 1/2

is not supposed to be 25% = 1/4 ?! bcz this is recurrence risk of AR
also you need to multiply the probability of the mother to be a carrier for the diseased allele because in the question they mentioned she is from the general population, so you dont know if she's a carrier or not...so you should calculate her carrier probability by using HW equation...

at the end u multiply all the probabilities
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Quote:
Originally Posted by excellence View Post
I got 0.05
Prevalence=q2=1/100 so q=1/10
Carrier freq= 2q=21/10=0.2

Probability man transmit dis allele=1/2
Probability woman is a carrier=0.2
Probability woman transmit dis allele= 1/2

Multiply....1/20.21/2= 0.05
Did you asume p =1 in your calculations? So carrier frequency is 2pq =2x1x1/10
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Quote:
Originally Posted by dr_marini View Post
Did you asume p =1 in your calculations? So carrier frequency is 2pq =2x1x1/10
Yes I did.
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thank you.
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