maximal frequency of recombination

[theonlytycrane]

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Is the maximal frequency of recombination 50%? I was thinking that it could theoretically be 100% if all offspring are recombinants.

Also, is recombination frequency only applicable when genes are linked?

For reference: recombination frequency = # of recombinations / total # of offspring

 

[Thoroughbred_Med]

Yes, the MAXIMUM recom. frequency produced by two germ cells that sort completely independently is 50%. You can never have a greater frequency than this. This is the case for two genes on separate chromosomes or two genes that are far apart on the same chromosome, both defined as unlinked. The product (recombinants) of this independent assortment meiosis would result in the parental genotype exclusively.

For linked genes the frequency is between 0 and 50%, usually on the lower end.

 

[theonlytycrane]

If it is known that two genes are linked on the same chromosome and all offspring observed display phenotypes indicating recombination, wouldn't this result in a recombination frequency of 100%?

Example:

Male- Ab and aB

Female- ab and ab

All offspring: ab and ab (male recombination occurred)

I may be thinking of this incorrectly.