Genetic engineering, conceptual illustration. Robot hand editing a DNA (deoxyribonucleic acid) molecule to alter and rearrange an organism's genetic material. DNA is composed of two strands twisted into a double helix. Each strand consists of an outer sugar-phosphate backbone with nucleotide bases attached. The sequence of these bases forms the genetic code, determining each cell's structure, function and behaviour. Inserting new DNA into a section of original DNA will alter the instructions from this region.