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No one can predict what current discoveries will most shape tomorrowís industries. But the following synopses represent new research that is opening or closing doors to target validation, new therapeutic approaches, and genetically modified crops. We consider these recently published articles thought provoking.

Healthy Prices

Drug development costs have jumped.

Context: Even the most careful accountant would be at a loss to determine the total cost of bringing a new drug to market. Most projects fail to yield a drug at all, and development can take more than a decade. Research at the Tufts Center for Disease Development used detailed pharmaceutical spending data in a rigorous analysis to estimate costs. This study updates similar ones from 1979 and 1991.

A Knockout Library

rna interference screens function across animal genome for the first time.

Context: A genome sequence can identify how many genes an organism has, but not what the genes do. To know a geneís function, we must see what happens when that gene is silenced. In the roundworm Caenorhabditis elegans, Kamath et al. used RNA interference to inactivate, one at a time, 16,757 genes; more than half are homologous to human genes. This is the first genomewide functional screen of an animal.

Birds, Bees, and Bourgeonal

Receptor controls spermís direction, speed

Context: How egg and sperm find each other has occupied philosophers and scientists for centuries. Now a new study indicates that the way sperm find an egg may be similar to the way neurons in the nose detect scent molecules. Olfactory receptors (ORs), a family of signaling proteins, are located throughout the body, including in sperm and proto-sperm cells (where at least 40 ORs are expressed), driving speculation that ORs are involved in sperm chemotaxis. Spehr et al. provide evidence that this is the case.

Btr Growing Through Chemistry

GM cotton crops show higher yields.

Context: Genetic engineering has created crops resistant to pests and herbicides, but the yield advantages have been relatively small: in the United States and China, for instance, yield gains of genetically modified (GM) cotton crops are typically less than 10%. Now, publishing on genetically modified cotton trials in India, Qaim and Zilberman suggest that GM crops have far greater potential in the developing nations than in the nontropical countries for which they were designed.

Twist of Fates

Telomeres cut short are linked to increased aging.

Context: Telomeres, the repeating sections of DNA found at the ends of chromosomes, shorten in most human cells after each division—a process that ultimately concludes with senescence and apoptosis (programmed cell death). For a few unfortunate individuals, the normal rate of telomere shortening is drastically accelerated.

Brain Food

Transplanted bone marrow cells generate new neurons.

Context: Evidence has long indicated that adult stem cells, commonly harvested from bone marrow, can become various types of tissue; now evidence suggests they can become neurons as well. When Mezey et al. analyzed postmortem brain samples from human females who had, as treatment for various non-neurological immune disorders, received bone marrow transplants from male donors, the researchers found donor-derived neurons.

T Cell See, T Cell Do

Geron teaches immune systems to “see” cancer.

Context: Cytotoxic T cells (CTLs) that recognize cancer antigens are essential to preventing the disease. While all known tumor-associated antigens are specific to certain cancers, more than 90% of human tumors express high levels of telomerase. This enzyme maintains the DNA at the ends of chromosomes, allowing cells to divide indefinitely, and isnít active in most normal body cells (see “Twist of Fates,” above). Recently, Frolkis et al. exploited this difference by manipulating immune cells that train T cells to recognize and attack new antigens.

Polyp Quiz

Insurance and family concerns endanger the promise of genetic testing.

Context: One frustration with genetic testing is that the ability to diagnose disease often outpaces the ability to cure it. For certain cancers, identifying risks can lead to better monitoring and, thus, to earlier diagnosis. However, a known risk can also lead to increased anxiety or, potentially, discrimination. A better understanding of why patients choose or refuse genetic testing could be used to improve genetic counseling; Hadley et al. sought to elucidate patient attitudes about this technology.

A Few Bad Apples

Only a small crop of cancer cells seems to generate tumors.

Context: Breast cancer is the most common cancer in women. Itís also one of the most difficult to treat, because a single tumor contains various cell populations with incompletely understood compositions and functions. Competing hypotheses propose that only certain distinct cancer cells can give rise to a new tumor or, alternately, that any cancer cell can do so but that this happens rarely. Research by Al-Hajj et al. demonstrates that, at least in breast cancer, a tiny minority of cancer cells are able to generate tumors and that these cells can be accurately identified.

Mad Cow Mitigated

Monoclonal antibodies show efficacy against prion disease.

Context: are naturally occurring proteins that, if converted to an abnormal form, induce other prions to adopt that form. This causes disease, most famously the mad cow outbreak in Britain that killed dozens of people and nearly crippled the beef industry in Europe.

Though extremely rare, prion diseases are fatal and untreatable. Antibodies have previously shown potential to bind up prions in vitro, and mice genetically engineered to produce prion-specific antibodies are less susceptible to prion disease. In experiments more directly related to therapeutic solutions, White et al. found that regularly injecting prion-specific antibodies can delay disease in mice, seemingly forever.

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Synopses

Healthy Prices

A Knockout Library

Birds, Bees, and Bourgeonal

Btr Growing Through Chemistry

Twist of Fates

Brain Food

T Cell See, T Cell Do

Polyp Quiz

A Few Bad Apples

Mad Cow Mitigated

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