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  #1  
Old 05-27-2011
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Genetics Syndactyly Pedigree question

Syndactyly is a rare condition inherited as an autosomal dominant trait. Unusually however, a person who has the defective allele responsible for Syndactyly (N), does not always show the trait. The diagram below shows the pedigree of a family with Syndactyly:

Syndactyly Pedigree question-screen-shot-2011-05-27-9.10.59-pm.png
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There was no history of Syndactyly in the ancestors of individuals I-1, II-1 and II-6. Assuming that there are no new mutations, it is reasonable to conclude that:

a) Individual II-5 has the genotype nn
b) Individuals II-4 and II-5 may have the same genotype
c) Individual II-1 has the genotype Nn
d) Individuals III-2 and III-5 may have different genotypes
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  #2  
Old 05-28-2011
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I think the answer is B)...I'm no sure though
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  #3  
Old 05-28-2011
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somebody else want to answer this?
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Old 05-28-2011
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i think its C..
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Old 05-28-2011
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I think it is D
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  #6  
Old 05-28-2011
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Correct Answer Correct answer

Correct answer is B)
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Old 05-28-2011
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Quote:
Originally Posted by bebix View Post
Syndactyly is a rare condition inherited as an autosomal dominant trait. Unusually however, a person who has the defective allele responsible for Syndactyly (N), does not always show the trait. The diagram below shows the pedigree of a family with Syndactyly:

Attachment 1337
click image to enlarge

There was no history of Syndactyly in the ancestors of individuals I-1, II-1 and II-6. Assuming that there are no new mutations, it is reasonable to conclude that:

a) Individual II-5 has the genotype nn
b) Individuals II-4 and II-5 may have the same genotype
c) Individual II-1 has the genotype Nn
d) Individuals III-2 and III-5 may have different genotypes
i ll go for D
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Old 05-28-2011
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Quote:
Originally Posted by Amenah View Post
i ll go for D
here is the explanation:


I hope this help
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