What are the rules?

Genetics as it applies to evolution, molecular biology, and medical aspects.

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mensamedlem
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What are the rules?

Post by mensamedlem » Sat Mar 06, 2010 12:56 pm

What are the rules to state the genotype of the individuals in a pedigree like this?

Please explain it step by step of each individual so I understand the process.

Squares = men
Circles = women

Yellow = sick
Green = healthy

A = sick
a = healthy

a) What is the mode of inheritance? Why?

b) What are the genotypes of each individual?

http://img21.imageshack.us/img21/9991/pedigree.gif

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JackBean
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Post by JackBean » Mon Mar 08, 2010 6:44 am

it's apparently not dominant, because sick man has healthy children and vice versa.
There are only men sick, but from two brothers, one is sick and the other healthy, so it's probably not sex-linked.

With these info, try to figure out the rest ;)
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

mensamedlem
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Post by mensamedlem » Tue Mar 09, 2010 10:36 am

Then it must be autosomal recessive.

Are the genotypes correct?

A = sick
a = healthy

Generation 1:
AA - Aa/aa - Aa - Aa

Generation 2:
Aa - Aa - Aa - Aa/aa - AA

Generation 3:
AA

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JackBean
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Post by JackBean » Tue Mar 09, 2010 1:34 pm

yes, that seems fine to me. Although I would use a for sick and A for healthy, but that's your choice (just make it clear)
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

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