Antisense Technologies • antisense oligonucleotides(ODNs) • Ribozymes • DNAzymes • RNA interference(RNAi). Part of Gene Therapy
Gene Therapy... ----idea is to replace defective genes Gene therapy is a technique for correcting defective genes responsible for disease development.
Several approaches for correcting faulty genes • A normal gene may be inserted into a nonspecific location within the genome to replace a nonfunctional gene. • An abnormal gene could be swapped for a normal gene through homologous recombination. • The abnormal gene could be repaired through selective reverse mutation, which returns the gene to its normal function. • The regulation (the degree to which a gene is turned on or off) of a particular gene could be altered.
Deliver the therapeutic gene Some of the different types of viruses used as gene therapy vectors: • Retroviruses • Adenoviruses • Adeno-associated viruses • Herpes simplex viruses
Deliver the therapeutic gene Adenoviruses
Efficient delivery Enhanced stability Minimization of off-target effects Identification of sensitive sites in the target RNAs Challenge
Status of gene therapy • The Food and Drug Administration (FDA) has not yet approved any human gene therapy product for sale.
Gene Therapy in the clinic Trials Wordldwide 66% Phase I 21% Phase I-II 11% Phase II 0.8% Phase II-III 0.7% Phase III in spite of 13 year- research only less than 1% of the trials has reached phase III
For more details • Genetic Modification Clinical Research Information System (GeMCRIS) http://www.gemcris.od.nih.gov/