Quick Question-

[sa6588]

Hi, got a question that I'm a bit stuck on.

"The mutation that causes brachydactyly is present in every cell of the body, yet only the hands are affected. Write a short paragraph in which you explain why such a gene can only affect some cells of the body and not others."

I'm a bit clueless there i'm afraid - obviously not asking for a direct answer, but help would be very nice.

Also quickly- how can I deduce from a pedigree chart whether or not a genetic disorder is x-linked or related to a gene on an autosome? (given that it is of dominant character)

thanks for your time

[canalon]

Basicallly what you have to discuss is differential expression of genes during development, this is involved in cells differentiation but also in organ development (how come most human have only 2 arms, roughly located similarlyin their body plan...)