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  #1  
Old 06-09-2010
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Genetics Genetic Pedigree Question

Given this pedigree,
Genetic Pedigree Question-picture-5.png
click to enlarge

what would be expected of the III generation?


a) The probable pattern of inheritance shown by the disease in this family is autosomal recessive.
b) If recombination does not occur the probability that III 1 will be affected if she has an AB marker genotype is 1.
c) If recombination does not occur, the probability that III 1 will be affected if she has a BB marker genotype is 1.
d) If the recombination fraction between the disease and marker loci equals 0.04, the probability that III 1 will be affected if she inherits an AB marker genotype equals 0.96.
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  #2  
Old 06-10-2010
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I think its C

Last edited by inder; 06-10-2010 at 06:36 AM. Reason: accidently put B instead of C
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  #3  
Old 05-28-2011
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Any more thought on this? what do you think is the correct answer?
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  #4  
Old 05-28-2011
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Default D

Quote:
Originally Posted by usluipek View Post
Any more thought on this? what do you think is the correct answer?
its D i guess.. a probability of 1 means the child is definitely affected..
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Old 05-28-2011
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Quote:
Originally Posted by lynk View Post
Given this pedigree,
Attachment 824
click to enlarge

what would be expected of the III generation?


a) The probable pattern of inheritance shown by the disease in this family is autosomal recessive.
b) If recombination does not occur the probability that III 1 will be affected if she has an AB marker genotype is 1.
c) If recombination does not occur, the probability that III 1 will be affected if she has a BB marker genotype is 1.
d) If the recombination fraction between the disease and marker loci equals 0.04, the probability that III 1 will be affected if she inherits an AB marker genotype equals 0.96.
why not B)?
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Old 05-28-2011
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Quote:
Originally Posted by lynk View Post
Given this pedigree,
Attachment 824
click to enlarge

what would be expected of the III generation?


a) The probable pattern of inheritance shown by the disease in this family is autosomal recessive.
b) If recombination does not occur the probability that III 1 will be affected if she has an AB marker genotype is 1.
c) If recombination does not occur, the probability that III 1 will be affected if she has a BB marker genotype is 1.
d) If the recombination fraction between the disease and marker loci equals 0.04, the probability that III 1 will be affected if she inherits an AB marker genotype equals 0.96.
My answer is C)
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  #7  
Old 05-28-2011
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can anyone elaborate it in a detail?
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Old 05-28-2011
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Quote:
Originally Posted by struggle View Post
can anyone elaborate it in a detail?
I know that A) & D) are incorrect...but Im not sure if the right answer is C) or B)...I chose C, but I was guessing
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  #9  
Old 05-28-2011
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Lynk, could you tell us what is the right answer? :sorry:
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Old 05-28-2011
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i think its B....
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Old 05-30-2011
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I found the answer, but I don't understand why....HELP:sorry::sorry:

Correct answer:

c) If recombination does not occur, the probability that III 1 will be affected if she has a BB marker genotype is 1.

Feedback:

The pedigree points to autosomal dominant inheritance with two generation involvement and male to male transmission. II 2 has inherited both the disease and allele B from his father. Therefore if III 1 inherits allele A from her father the probability that she will be affected equals 0 if there is no recombination, or 0.04 if the recombination fraction = 0.04.
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