Sir — In the discussion of gene patents1, it is generally overlooked that these primarily aim at the encoded protein and not the gene. The discoverers try to patent the use of the ‘gene product’ either as a therapeutic protein, or as an intervention point (‘drug target’) to treat a disease.
However, although the gene sequence provides necessary information on the protein structure, this information is insufficient, because the mRNA and the original gene product, the protein, are modified in an unpredictable way depending on the temporal and spatial context of their biosynthesis. Who could have predicted the active form of insulin from its gene? Also, the co-receptor of HIV, CCR5, on which a controversial patent has been issued2, appears to be a co-receptor for HIV only if it is modified by attachment of sulphate residues3. It is evident that, if a patent covers a ‘gene product’, it should only give rights on the predicted, unmodified form. Experimental evidence for the existence of the predicted function of the gene product should be provided.
What about patenting gene products as drug targets? The EU patent directive states clearly that the human body and its components in their native environment cannot be covered by a patent. What is a drug target other than a component of the human body in its native environment? This statement can only mean that drug targets are not patentable in Europe, otherwise it would be nothing but a political declamation.
There are other problems with patenting drug targets. Many drugs are still discovered using animal model systems or cellular assays. In the United States, for example, the National Institutes of Health has a number of screening programmes using mice to detect anti-epileptic compounds, and cell cultures to detect cytotoxic compounds, where the molecular target is unknown. If a scientist or a company discovers a drug using such an assay, they would be stupid to try to identify the drug target, because there is some likelihood that the drug target is already covered by a patent. Patenting drug targets is therefore scientifically counterproductive: it enforces a culture of ‘not wanting to know’.
Let's assume that drug targets can be patented in the United States but not in Europe. As a consequence drugs could be developed unrestrictedly in Europe but not in the United States. US companies would then be forced to move their drug discovery and development to Europe. Still these drugs could not be used in the United States. As a result patients would have to travel from the United States to Europe to receive their life-saving drug. What a great perspective for Europe's biotechnology and economy!