internal tandem duplication
(in-TER-nul TAN-dem DOO-plih-KAY-shun)
A type of genetic change in which a DNA sequence in a gene is copied and inserted right after the original DNA sequence. This changes the sequence of the gene, which can affect the function of the protein made from the gene. Internal tandem duplications are associated with certain types of cancer, such as acute myeloid leukemia. Also called ITD.