Question

Why are microdeletions and microinsertions difficult to diagnosis using karyotyping?

Answer 1

Because only the chromosomes can be seen in a karyotype, and microdeletions or insertions are mutations at the molecular level, it is virtually impossible to detect such mutations at the chromosomal level. 

Answer 2

Answer & explanation:

Mutations that occur by microinsertions or microdeletions (usually a pair of nitrogenous bases) can result in a change in the reading phase of the gene, completely modifying its translation into a particular protein.

Microinsertions are responsible for inserting a nucleotide into the DNA sequence, while microdeletions remove a nucleotide from the DNA sequence.

Diagnosing microdeletions or microinserts is highly difficult and requires highly skilled professionals, since many of the detected changes represent variations in copy number without clinical significance or of unknown clinical significance.