I'm certainly no expert in recombination but I can give you an example of sites
where recombination can be very frequent (up till a 100 %). I'm studying
gyonogenesis in an African catfish species (Clarias gariepinus). Gyonogenesis
is a reproduction method by which you can produce offspring containing genetic
material from the female only. To obtain this offspring you have to detroy the
father's genetic material (by U.V.-irradiation) and use this sperm to activate
the eggs. These resulting embryos are haploidand not viable. By applying a
shock (in temperature for example) you can restore diploidy however. This is
obtained thru the retention of the second polar body (and its genetic material)
which, in fish, is extruded normally after the activation of the egg.
So far for induced gynogenesis. If recombination at a certain loci happens
during this process, and if the female is heterozyous, the gynogenic offspring
will be heterzygous as well. So by genotyping the parents and offspring we
showed that for at least one of the microsatellite markers (non-coding DNA) we
use that the recombination frequency is a 100 %. This fenomen has been describ
ed in articles using similar methods. An adequate explanation hasn't been foun
d as far as I know. Someone has a suggestion?