Question

You perform interrupted conjugation using an a⁺b⁺c⁺d⁺e⁺f⁺g⁺h⁺ Hfr strain and an F^– strain that is a^–b^–c^–d^–e^–f^–g^–h^–. You observe the following genes transferred together in order from last to first:                              

                                 h⁺b⁺g⁺d⁺

e⁺f⁺d⁺g⁺

f⁺e⁺a⁺c⁺

      What is the map order of the genes?

Answer 1

ANSWER

Let us label the fragments as 1, 2 and 3.

1 →   h⁺ b⁺ g⁺ d⁺

2 →   e⁺ f⁺ d⁺ g⁺

3 → f⁺ e⁺ a⁺ c⁺

Now let us try to overlap the fragments. If you observe, you’ll notice that fragment 2 does not overlap with the other two fragments. Therefore, we need to invert fragment 2.

htbt gt dt gt d+ ft et ft et at ct

From the above comparison, we can conclude that the map order of the genes is:

h⁺ b⁺ g⁺ d⁺ f⁺ e⁺ a⁺ c⁺