Psychiatric Gene Researchers Urged to Pool Their Samples

If geneticists want to make more progress toward pinpointing psychiatric genes, they will need to pool their DNA samples. This theme was often reiterated during the 15th World Congress on Psychiatric Genetics, held in New York City in October (see Original article: Obstacles Hinder Search for Mental Illness Gene).

The challenge, essentially, is that a plethora of genes with small effects—not just one dominant gene with a large effect—seems to underlie psychiatric illnesses. Or as Hugh Salter, Ph.D., from AstraZeneca Research and Development stressed, “The largest problem that faces us is the small effect size for single genes.”

Moreover, the major tool that geneticists wield today to pinpoint psychiatric genes is the genome-wide association study, in which the DNA of persons afflicted with a particular psychiatric illness is compared with the DNA of healthy control subjects. Yet to identify small gene effects in such studies, one may well need to use DNA taken from thousands of subjects, Francis Collins, M.D., Ph.D., director of the Human Genome Project, stated.

Thus, pooling DNA samples for genome-wide association studies would enhance geneticists' statistical power to ferret out psychiatric genes.

Some psychiatric geneticists are starting to pool their DNA samples. For example, Pamela Sklar, M.D., Ph.D., an associate professor of psychiatry at Harvard Medical School, reported that she and her colleagues have started putting their DNA material together with DNA material obtained by British scientists to speed the identification of bipolar disorder genes.

If academic geneticists want to accelerate the unmasking of psychiatric genes, they may want to share DNA samples with drug-company geneticists as well, some speakers suggested. For instance, as Bryan Dechairo, Ph.D., head of neuroscience molecular medicine at Pfizer Global Research and Development, reported, Pfizer does not lend DNA samples to academic geneticists. But Pfizer is willing to provide academic geneticists with information about those samples.

Such academia-industry DNA sharing may be tough to bring off, however, several geneticists cautioned. For instance, Lynn DeLisi, M.D., a professor of psychiatry at New York University and chair of the psychiatric genetics congress, said that she once shared her DNA samples with a drug company,“ and it ended in a disaster for my career.” The company with whom she had collaborated was bought by another company, and it took her a long time to get her DNA samples back. Scientists at drug companies are“ terrific,” but once the lawyers get involved and draw up contracts, that is when the trouble starts, she said.

Another reason why academic geneticists and drug-company geneticists may have trouble sharing DNA material is because they have different missions, David Porteous, Ph.D., chair of human molecular genetics and medicine at the University of Edinburgh in Scotland, pointed out. The former want to use the material to identify psychiatric genes, while the latter want to deploy it to develop new drugs. ▪