New study suggests genetic makeup affects smallpox vaccine effectiveness

A new Mayo Clinic study suggests that a person's genetic makeup affects the effectiveness of the smallpox vaccine and can have implications for individualizing the vaccine development process.

Findings from the genomic screening, conducted by the Mayo Clinic to test the smallpox vaccine's effectiveness, were published in the Genes and Immunity journal on Friday. Researchers found that individual genes altered the response of the vaccine and autoimmune response against a smallpox-like infection, vaccinia.

"We were looking into the intercellular reactions that occur when vaccinated and unvaccinated persons are exposed to and infected with smallpox virus," Director and Senior Author at the Mayo Clinic Vaccine Research Group Gregory Poland said. "We could see what would happen based on exposing a mixed-cell peripheral blood cell population to the vaccinia virus."

The study took 44 participants from the Naval Health Research Center and the Mayo Clinic that had already received the smallpox vaccine 48 months prior and studied how a vaccinated and unvaccinated group responded to a vaccinia infection. Ribonucleic acid, the molecular form of DNA, was tested after infection for sequence; genetic differences were found amongst those with high and low autoimmune responses.

Poland said this offers new insight into how to approach medicine on an individualized level, and that this gives researchers a target for developing vaccines to better those that did not respond.

Smallpox remains a bioterrorism threat and vaccination is accepted worldwide as a measure for eradication.