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Discussion Starter · #1 ·
this is a gentics question on concordance:
 

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Discussion Starter · #4 ·
answer to the concordance rate question is attached its D
 

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Please

answer to the concordance rate question is attached its D
there is two relationship in the answer relating concordance rate to DZ n MZ twin and result being autosomal dominant or recessive.
anybody know how you drive this relation?

here is how i came t answer-
since the risk in MZ is 40 the answer must be less than this
leaves three option
but as the parents already have a child with the sickness the risk in second is for sure higher than general population
that leaves with two option
and second child gentically not that unsimilar to having DZ TWIN my answer would be more close to that.
if anything wrong with thinking .please please do point it out.:eek:

also in end of explanation-if it AUTO recessive why MZ is 100% without pointing that both parents are homozyg. and sick. right
and how DZ is 25% how??????:toosad::toosad::toosad::toosad::toosad::toosad::toosad:
 

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thx!!

i didnt apply this rule. i just calculated the odds of a second child having cleft lip and ignored the fact whether it could be AR or AD.

luckily for ur question, i know a little bit more than i did yesterday.:)
 

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thx!!

i didnt apply this rule. i just calculated the odds of a second child having cleft lip and ignored the fact whether it could be AR or AD.

luckily for ur question, i know a little bit more than i did yesterday.:)
where is it given?
i dont understand how its decide not AR or AD in question.:toosad::notsure:
 

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where is it given?
i dont understand how its decide not AR or AD in question.:toosad::notsure:
i think the question wants us to decide for ourselves whether or not it is AR or AD. if its AR, then DZ rate will be 25% of MZ. if it were AD, then it would be 50% of MZ. n if these rules applied, u apply one famous formula:
concordance rate = (MZ - DZ)/(100 - DZ)

then if he is having second child, u times the results u get twice (ie: 0.5 x 0.5 = 0.25 = 25%)

but thats not the case here. it's neither AR nor AD. so we have to decide that its more than the population n less than MZ n based on that information alone, pick an answer.

am i making any sense?:eek:
 
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