Biology - Calculating map distance of genes
Calculating map distance of genes
* Linked genes are those on the same chromosome  but at different loci
* The closer together genes are on the same chromosome the less likely
crossing over will occur
* The further apart the loci of the genes are the more likely crossing
over  will occur
* A crossing over frequency of 1% represents a distance of 1 map unit
* Parents of known genotypes  are crossed to determine the number of
parental and recombinant phenotypes  in the offspring.
If the cross over frequency between genes D and G is 32% then genes D and
G are 32 map units apart on the chromosome.
Through deliberate matings or trial and error, a map of a chromosome can
be built up. In 1999, one human chromosome was mapped completely, though
not by deliberate matings or trial and error!
Previous | Next