Login

Join for Free!
118822 members


Don't understand recombinant chromosomes

Discussion of all aspects of cellular structure, physiology and communication.

Moderator: BioTeam

Don't understand recombinant chromosomes

Postby WiseIdiot » Wed Oct 22, 2008 4:58 pm

Why is crossing over likely to occur when genes are located further apart? I do not see the connection between one gene and another gene located on the same chromosome and what that has to do with crossing over. i thought crossing over was mainly between alleles of the same gene across two homologs. This seems irrelevant to the presence of another gene.
WiseIdiot
Garter
Garter
 
Posts: 8
Joined: Sat Oct 18, 2008 5:51 pm

Postby Daniel01 » Mon Nov 24, 2008 5:38 pm

Because there is some crossing over of DNA when the chromosomes segregate, alleles on the same chromosome can be separated and go to different daughter cells. There is a greater probability of this happening if the alleles are far apart on the chromosome, as it is more likely that a cross-over will occur between them.

The relative distance between two genes can be calculated using the offspring of an organism showing two linked genetic traits, and finding the percentage of the offspring where the two traits do not run together. The higher the percentage of descendants that does not show both traits, the further apart on the chromosome they are.
Wikipedia http://en.wikipedia.org/wiki/Genetic_linkage
Daniel01
Garter
Garter
 
Posts: 12
Joined: Mon Nov 10, 2008 4:31 pm


Return to Cell Biology

Who is online

Users browsing this forum: No registered users and 5 guests