Name: Deven Mistry
This is genetics question: I would like to know how someone can come up
with a recombinance map using map units for a trihybrid testcross?
(Sorry I do not have any more info on the question.)
By doing a trihybrid testcross and looking at the number of
offspring with expected gene combinations versus the number with
unexpected gene combinations, one can calculate the map unit
distance between those genes. These map units do not represent
actual distances on chromosomes, but rather show how frequently
crossing over might occur during meiosis. The reasoning is that
the closer two genes are on a chromosome, the less likely they are
to be separated during crossing over. Since all three genes in
your trihybrid are presumably on the same chromosome, they should
stay together in the offspring, except where crossing over occurs.
Does that make sense, or do you need more background?
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Update: June 2012