In a threepoint linkage analysis the RF values for genes A B

In a three-­point linkage analysis, the RF values for genes A, B and C were determined as the following: A-­B (RF=35%), B-­C (RF=32%), A-­C(RF=50%). Please explain if this analysis identifies the gene located in the middle and describes the chromosome distance between each pair of the three genes in cM

Solution

RF means recombination frequency.

RF analysis determined the gene order , They can give a basic idea about the position of the genes , however when combined with molecular and cytological analysis can provide more precise locations.

The RF of less than 50 shows that the genes are linked, for A-B the RF is less than 50% so they are linked , same is with B-C but for A-C it is 50% which means they are not linked,

So it gives a basic idea that B is in the middle which have the linkage with both A and C but A and C are far apart as they are not linked

So this is how the problem can be solved and gene location can be determined by RF