The subsets of approximately 30,000 genes in the human genome that can bind to drug like molecules by expressing proteins are called as “The Druggable Genome”. This concept is raised because of the limitation of molecular targets for which commercially viable compounds can be developed. This means that “The Druggable Genome” which has the ability to produce proteins to bind with drugs.
Commercially viable drug means an orally bioavailable compound. Physico-chemical properties are necessary to improve the oral bioavailability of drug which can be formalized by the Lipinski “rule of five” analysis. Most successful drug achieves their activity by searching for a binding site on protein with a small endogenous molecule. It is necessary that a drug must bind to its target molecule with a reasonable potency, to be more effective.
Survey has been taken to find the molecular targets for a drug to bind on its binding site. Analysis of International Drug Database and the Pharmaprojects Database recognise 399 non-redundant molecular targets. In that, several proteins are targeted by experimental drugs and some are eliminated because of its inactivity according to the rule of five analysis. Most of the drugs identified in this survey are competitive. Those targets fall into the six gene families:
· G-protein Coupled Receptors (GPCRs)
· Serine/Threonine and Tyrosine protein kinases
· Zinc metallo-peptidases
· Serine proteases
· Nuclear hormone receptors
New methods such as protein drugs, antibody therapies, DNA vaccines and non-oral drug delivery systems, could expand the range of potential targets those which can’t be identified by rule of five analyses. The limited number of molecular targets for the drug suggest that the druggable genome to be produced in a cost-effective manner. This will be the major innovation for the pharmaceutical industry, not just in the case of science, but also in the case of business.