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#1




Genetic Pedigree Question
Given this pedigree,
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. 
#2




I think its C
Last edited by inder; 06102010 at 07:36 AM. Reason: accidently put B instead of C 
#3




Any more thought on this? what do you think is the correct answer?

#4




D
its D i guess.. a probability of 1 means the child is definitely affected..

#5




Quote:

#6




Quote:

#7




can anyone elaborate it in a detail?

#8




I know that A) & D) are incorrect...but I´m not sure if the right answer is C) or B)...I chose C, but I was guessing

#9




Lynk, could you tell us what is the right answer? :sorry:

#10




i think its B....

#11




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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