The organisers of the masterclass on toxicogenomics and bioinformatics interpreted the definition of a masterclass quite literally. The participants were taught by two ‘masters’, Rob Stierum, toxicologist at TNO Zeist, and Perry Moerland, bioinformaticist at AMC Amsterdam, and even had to prepare and present their homework.

Endpoint

The week before GRE2007 the participants received two scientific papers and some questions to think about. The masterclass started with a few presentations in which participants presented their resulting ideas. According to them, toxicogenomics is more than a way of reducing the number of animal tests, as it supplies scientists with additional information. It gives not only an endpoint, but also the pathway by which this can be reached.

Gene sets

Rob Stierum stated that in recent years, toxicology has become more and more molecular in nature, while regulatory toxicology stayed behind. It is time for a change, according to Stierum. Perry Moerland explained that there are four directions in which research in this field is developing. The most important development is that genetic analysis is performed increasingly on gene sets instead of single genes. Such a gene set can be a group of genes that all function within the same pathway or are located on the same chromosome. Gene set analysis has the advantage of being more sensitive, more robust and less hampered by noise.

Combine data 

Moerland showed an example of diabetes, where the effect of single genes was quite small, but the combination clearly showed a trend. Furthermore, this type of analysis makes it easier to combine data from different labs, which is the second development that Moerland mentioned. Other developments are the combination of data from different organism and from different techniques.
 

Different organisms

In the final discussion, the value of toxicogenomics was questioned, considering that the sensitivity appears to be similar to or even worse than traditional methods. One of the participants mentioned the example of ecotoxicology. In this field, the traditional methods were limited to a few different organisms, whereas toxicogenomics enables tests for numerous different organisms. Moerland presented another example. Using toxicogenomics, the duration of traditional tests on carcinogenesis, which normally take two years, can be reduced.

 

[Els van den Brink]