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Hello! I need help with this exercise question. I am not really sure which pedigree diagram is autosomal and which is not. But, is question b 1/2. Can someone give an explanation? Thanks very much in advance? Appreciate any help!!

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marked as duplicate by biogirl, Chris, WYSIWYG, Satwik Pasani, Atl LED Jan 28 '14 at 2:58

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

According to the key given, the one shaded black on the right is autosomal and one on the left is sex linked.

Yes, the answer to b is half because Maria is XhX ans Peter is XY and so the probability of the child having this disease is 1/2.

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@ApothemCyte Does this make sense ? Ask, if u need help ! – biogirl Jan 26 '14 at 18:33
Thanks for the reply! But if the the diagram on the right is concerned with an autosomal disease, shouldn't we use Gg/gg/GG notation in place of XhX (for Maria). – ApothemCyte Jan 26 '14 at 19:49
Also, I'm a little bit unsure as to whether the genotypes I have for the diagram are actually correct. So, a brief explanation would help. Thanks in advance! – ApothemCyte Jan 26 '14 at 19:51
ApothemCyte, the diagrams are concerned with both the autosomal disease and the X-linked disease; look at whether the person symbol is shaded on the left side or the right side. – mgkrebbs Jan 26 '14 at 21:18
@mgkrebbs So here is my 2nd attempt. Do they look right now? (even to a person with no formal training) link:… – ApothemCyte Jan 27 '14 at 2:01

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