Solutions For An Introduction to Genetic Analysis Chapter 17 Problem 39P

A very large pairing loop is observed at meiosis. Such a large loop cannot be due to heterozygous deletions. Deletions of large fragments cause instability in the genome and can reveal lethal genes.

A heterozygous inversion can be the reason, for large pairing of loop. In the process of inversion, two breaks occur in the genome. This results in the fragment between the cuts to loop out. This could be the reason, for large fragment to be seen in meiosis.