Suppose a three-point testcross was conducted involving genes X, Y, and Z.If the most abundant classes of progeny are X Y z and x y Z and the rarest classes are x Y Z and X y z, which gene is in the middle?
A)X
B)Y
C)Z
D)cannot be determined

Question

Quizplus · Accepted Answer

The gene in the middle can be determined by looking at the rarest classes of progeny. In this case, the rarest classes are x Y Z and X y z, which differ by the exchange between the Y and Z genes, indicating that gene Y is in the middle.

Suppose a Three-Point Testcross Was Conducted Involving Genes X, Y