You Are Studying a Particular Gene in Mice

Multiple Choice

You are studying a particular gene in mice. In one sample of the genome from a mouse, you find two copies of the gene while in other mice you have studied there are two copies of the gene. One of the copies is in the normal location; the other is in a completely different location in the genome. The copy of the gene found in a different location from what is normal is bounded by sequences that are directly repeated rather than being in an inverted form. What is responsible for this finding?

A) a retrotransposon
B) a DNA transposon
C) a point mutation
D) a chromosomal inversion
E) an unequal cross-over