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Given this pedigree,
Rectangle Slope Font Parallel Pattern

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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Given this pedigree,
View 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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Given this pedigree,
View 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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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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