Pedigree help

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mensamedlem
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Pedigree help

Post by mensamedlem » Thu Oct 22, 2009 3:35 pm

I need help to find the answer to the questions below this text:

1) How is the inheritance?

2) Which genotypes do the persons have?

Source: http://www.flickr.com/photos/[email protected]/4035026508/

Can you help me?

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JackBean
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Post by JackBean » Thu Oct 22, 2009 11:58 pm

You mean, what kind of inheritence, right? ;)
Anyway, it seems to be recessive (as son of yellow isgreen, but his son is yellow again)
from left to right and from top down ;)
aa ... AA ... aA ... aA
aA ... aA ... aA ... aA or AA ... aa
aa

EDIT just did the scheme more clear, hopefully :)
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

mensamedlem
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Post by mensamedlem » Fri Oct 23, 2009 12:28 pm

Yes I mean what kind of inheritence.

Could it not be both autosomal recessive and x-linked recessive?

mensamedlem
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Post by mensamedlem » Fri Oct 23, 2009 8:26 pm

I have written this:

It is X-linked recessive.

As you can see, only males inherit the disease. This is because they only have one X chromosome so if they inherit the affected X chromosome then they are guaranteed to express the characteristic.

Females can inherit one affected X chromosome and one unaffected X chromosome and since the characteristic is recessive, it will not present itself in females. However, the females can pass the affected X onto their sons, who will exhibit the characteristic.

It is possible for the female to get two affected X chromosomes so she'll exhibit the characteristics but it is much more likely that a male will inherit one affected X chromosome than a female inheriting two.

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JackBean
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Post by JackBean » Sat Oct 24, 2009 11:45 am

yeah, I was also thinking, that it could be X-linked, but there is one man, whose child is ill. But it's true, that the boy would get from his father the Y chromosome, actually. Unfortunatelly, I can't access the photo now, to recheck it.
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

mensamedlem
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Post by mensamedlem » Sat Oct 24, 2009 6:24 pm


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JackBean
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Post by JackBean » Sun Oct 25, 2009 7:52 am

Well, yeah, I think both could work in this case
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

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