Modern medicine has come a long way. We can treat pneumonia, hypertension, diabetes, and even heart failure—but certain genetic diseases have proved more difficult to deal with. That may change in the near future with the application of techniques pioneered by Paul Zamecnik (b. 1912).
The use of genetic manipulation has had a place in medicine for quite some time in the form of recombinant DNA. This technique has been the source of many medicines, but is not really manipulation of genetic material in an individual. Zamecnik, though, may have revolutionized gene therapy, not by inserting new genes into an individual, but by blocking the genes that were already there. While studying a virus prone to causing certain cancers in chickens, Zamecnik realized that rather than adding a gene, he could manipulate the viral RNA so that it would not be able to reproduce. He figured he could take advantage of the fact that most genetic material, be it DNA or its cousin RNA, exists as a series of nucleotides that at some point pair up with other nucleotides. Zamecnik believed that if he could determine how to block that step, he might be able to prevent any number of bad outcomes.
In a study published in 1978, Zamecnik showed how one could prevent the normal function of a gene using a short strand of DNA that contained the base pairs opposite to the ones on the first strand. These strands, called oligonucleotides, tend to attach to the- first strip and block any translation of genetic material. The technology, called antisense, is now in development for the treatment of everything from leukemia to malaria.
