Searching nature's treasure trove for potential medicines is often only the first step. Having tapped natural resources to hunt for new medicines, pharmaceutical scientists then work to figure out ways to cultivate natural products or to make them from scratch in the lab. Chemists play an essential role in turning marine and other natural products, which are often found in minute quantities, into useful medicines.
In the case of Yondelis, chemist Elias J. Corey of Harvard University in Boston, Massachusetts, deciphered nature's instructions on how to make this powerful medicinal molecule. That's important, because researchers must harvest more than a ton of Caribbean sea squirts to produce just 1 gram of the drug. By synthesizing drugs in a lab, scientists can produce thousands more units of a drug, plenty to use in patients if it proves effective against disease.
Scientists are also beginning to use a relatively new procedure called combinatorial genetics to custom-make products that don't even exist in nature. Researchers have discovered ways to remove the genetic instructions for entire metabolic pathways from certain microorganisms, alter the instructions, and then put them back. This method can generate new and different "natural" products.
Toxicogenetics: Poisons and Your Genes
Just as your genes help determine how you respond to certain medicines, your genetic code can also affect your susceptibility to illness. Why is it that two people with a similar lifestyle and a nearly identical environment can have such different propensities to getting sick? Lots of factors contribute, including diet, but scientists believe that an important component of disease risk is the genetic variability of people's reactions to chemicals in the environment.
On hearing the word "chemical," many people think of smokestacks and pollution. Indeed, our world is littered with toxic chemicals, some natural and some synthetic. For example, nearly all of us would succumb quickly to the poisonous bite of a cobra, but it is harder to predict which of us will develop cancer from exposure to carcinogens like cigarette smoke.
Toxicologists are researchers who study the effects of poisonous substances on living organisms. One toxicologist, Serrine Lau of the University of Texas at Austin, is trying to unravel the genetic mystery of why people are more or less susceptible to kidney damage after coming into contact with some types of poisons. Lau and her coworkers study the effects of a substance called hydroquinone (HQ), an industrial pollutant and a contaminant in cigarette smoke and diesel engine exhaust. Lau is searching for genes that play a role in triggering cancer in response to HQ exposure. Her research and the work of other so-called toxicogeneticists should help scientists find genetic "signatures" that can predict risk of developing cancer in people exposed to harmful carcinogens.