A type of mutation that results in a change in the DNA sequence is called a genetic mutation. Mutations can occur due to various factors, including environmental radiation, chemical exposure, or errors during DNA replication. They can be classified into categories such as point mutations, which involve a change in a single nucleotide, while frameshift mutations involve the insertion or deletion of nucleotides that alters the reading frame. Some mutations can lead to genetic disorders, while others may have no noticeable effect.