The significance of the double helix structure in DNA lies in its ability to store and transmit genetic information. This structure, discovered by James Watson and Francis Crick, consists of two intertwined strands that are held together by hydrogen bonds between complementary bases. The double helix allows for the precise replication of DNA during cell division and provides a mechanism for mutations and genetic variation. Furthermore, it protects the genetic code from damage while allowing access to the information when needed for protein synthesis.