Axel, along with microbiologist Saul J. Silverstein and geneticist Michael H. Wigler, discovered a technique of cotransformation via transfection. This process, which allows foreign DNA to be inserted into a host cell to produce certain proteins, is fundamental to recombinant DNA research at pharamceutical and biotech companies. Order of authorship in the original publication: Wigler, ...Silverstein, Axel.

"In their landmark paper published in 1991, Buck and Axel cloned olfactory receptors, showing that they belong to the family of G protein coupled receptors. By analyzing rat DNA, they estimated that there were approximately one thousand different genes for olfactory receptors in the mammalian genome. This research opened the door to the genetic and molecular analysis of the mechanisms of olfaction" (Wikipedia article on Richard Axel, accessed 7-22).

In 2004 Axel and Buck received the Nobel Prize in Physiology or Medicine "for their discoveries of odorant receptors and the organization of the olfactory system."