DNA from a bacterial strain that is his leu lac is used to t

DNA from a bacterial strain that is his+ leu+ lac+ is used to transform a strain that is his- leu-lac-. The following percentages of cells were transformed: Donor Strain Recipient Strain Genotype of transformed cells Percentage his+ leu+ lac+ his- leu- lac his+ leu+ lac+ 0.02 his+ leu+ lac- 0.00 his+ leu- lac+ 2.00 his+ leu- lac- 4.00 his- leu+ lac+ 0.10 his- leu- lac+ 3.00 his- leu+ lac- 1.50 What conclusions can you make about the arrangement of these three genes on the chromosome? The leu gene is in the middle. and his and leu are closest. The lac gene is in the middle, and leu and lac are closest. The lac gene is in the middle, and his and lac arc closet. The his gene is in the middle, and his and lac are closet. The his gene is in the middle, and his and leu are closet

Solution

The answer must be Lac gene in the middle , His and lac are closest. If His in the middle then you should get some amount of recombinants for HIs and leu because leu is far away. But what you get is 0.10% of lac+ and leu+ so lac+ should be in the middle . Leu and lac are farther apart and that is why you get 0.10 % recombinants. His and lac are close so that you get 2% recombinants. So answer must be option 3.