These elements are called transposons. Our DNA is highly condensed in the nucleus. The primary packaging is done by histone proteins. These are small basic proteins that are probably the most conserved proteins in evolution. B. Mutations disrupt gene function either by disrupting transcription, splicing and translation or by changing the amino acid sequence in the encoded protein.
Missense mutations alter the amino acid sequence.
The best known missense mutation is the one the gives rise to sickle cell anemia. It is a single base change in the sixth codon of the beta globin gene that changes a glutamate to a valine. Frameshift mutations alter the reading frame by inserting or deleting any number of bases that are not divisible by three. Nonsense mutations change an amino acid coding codon to become a stop codon. Promoter defects alter the signals that control the translation of a gene.