Scientists Restore Sense of Smell Using Gene Therapy

Can you imagine what it would be like to never have had a sense of smell? Those born with congenital anosmia have never smelled a rose, or freshly popped popcorn, chocolate, or any of the smells that inform and enrich our lives. Now, for the first time, scientists have discovered a way to possibly give this missing sense to those without a sense of smell.

Scientists at the University of Michigan Medical School, working with colleagues at other schools, were able to restore the ability to smell to mice. The mice had a genetic defect which negatively impacted the cilia throughout their bodies. Cilia are instrumental in smelling and also affect other body parts and their functions, like the eyes and kidneys. The researchers used gene therapy to spur the olfactory neurons to regrow the cilia.

The mice were injected with the virus that causes the common cold that had the normal IFT88 genes loaded in it. When the mice got the virus, the gene loaded into their DNA. Within 2 weeks, they had a 60% increase in their body weight, an indication that they were eating more which is linked to a better sense of smell.

The therapy, which will not be available to humans for years, only addresses anosmia caused by cilia dysfunction, not that caused by head trauma, aging or chronic sinus problems. Because cilia dysfunction also causes other, more serious diseases, the therapy could be used to treat a host of other problems. Smells promising!