In: Biology
If the interference value is 1, then what is the probability of recombination between genes A and B if there is a recombination between genes B and C, where the gene order is A-B-C, the recombination fraction between A and B is 0.05, and recombination fraction between B and C is 0.15?
A. 0
B. 0.20
C. 1
D. 0.15
E. 0.05
ANSWER :- a.) 0
Interference is a interaction, in which the crossovers in adjacent chromosome regions are not independent. It gives the value of crossover coincidence with another crossing over in the same pair of chromosomes. Interference is related with the coefficient of coincidence. The coefficient of coincidence ( c.o.c ) decrease the cross over probability, if other genes are involved in crossing. The interference value therefore ranges from 0-1. Value less than 1 indicates that the interference is occurring in the same region of chromosomes.
If the interference (I) is maximum, I e. 1. Then the chances of double crossover is less or no chances of double crossover, while I= 0, then there is the maximum chance of double crossover.
In the above given questions, the interference value is given as 1, it means the probability of recombination between genes A and B is 0, as there is recombination between genes B and C.
So, interference value (I) is 1, there probability of recombination between genes is 0.