If a fragment of a chromosome breaks off and then reattaches to the original chromosome at the same place but in the reverse direction, the resulting chromosomal abnormality is called .

Chromosomal inversion

If a fragment of a chromosome breaks off and then reattaches to the original chromosome at the same place but in the reverse direction, the resulting chromosomal abnormality is called chromosomal inversion.

Explanation:

Chromosomal inversion is reversing the orientation of a chromosomal segment. It is one of the main causes of large-scale mutation.