If we have a chromosome with three loci in which the distanc

If we have a chromosome with three loci in which the distance between the loci is as indicated, then the probability of a double cross-over is A. 0.900 B. 0.016 C. 0.180 D.O 0.081

Solution

As per the question, the distance between loci cv and st is 9 m.u., it indicates that the probability of exchange of gametes between the two loci is 9% or 9/100 or 0.09. Similarly, the distance between loci st and 1x is 18 m.u., indicating the probability of exchange of gametes between the two loci as 18% or 18/100 or 0.18.

As per the \"product rule\", the percentage of expected double crossover is analyzed by multiplication of probability of exchange of gametes in one region by the probability of exchange of gametes in the other region.

Therefore, the probability of double crossover is 0.09 * 0.18 = 0.0162

The answer to the above question is B) 0.016