Please help 1 From a series of twopoint crosses the followin

Please help!

1. From a series of two-point crosses, the following map distances were obtained for the synthetic genes A, B, C, and D in peas:

B<--->C 23 m.u.
   A<--->C 15 m.u.
   C<--->D 14 m.u.
A<--->B 12 m.u.
   B<--->D 11 m.u.
   A<--->D 1 m.u.

Chi-square anaylsis cannot reject the null hypothesis of no linkage for gene E with any of the other four genes.

a. Draw a cross scheme that would allow for you to determine the B<--->C map distance.
b. Diagram the best genetic mad that can be assembled from this database.
c. Explain any inconsistencies or ambiguities or unknown features in your map.
d. What additional experiments would allow you to resolve these inconsistencies or ambiguities?

Solution

a. The probable scheme of genes is b----a----d----c.

b. The genetic map is b--12--a--1--d--14--c.

c. The reason for ambiguiteis betweent the gene map is the interference.

d. Molecular and physical gene mapping is best expriments along with gene tagging to resolve these ambiguities.

Explanation:

when ever we are dealing with two genes in genetics, in general we won\'t face the problem with interference. If we deal with morethan one gene then we will face the phenomenon is called interfernce. Interfernce means suppressing the formation one crossing over by another.

This interference affects the percentage of recombination. Due to this we will get the less value when compared to the actual distance.

Here, in this problem
the genetic map is b--12--a--1--d--14--c.

If you take the first three genes, the individual distance between b and a is 12 and a and d is 1. But if you take the distance between b and d it is 11. Actually it should be 13, but practically it would ne little low when comparing with actual data due to interference.

as like this, the distance between b and c is 23, but actually ot is 27. This is also due to interference.

Still if you have any quiry comment me.